[Enhancement](BRPC)enlarge brpc_max_body_size to avoid connection killed

[GoGoWen]

What problem does this PR solve?

In our env(180BE), the default brpc_max_body_size(3G) is not OK, which cause query/load failed. change it to 6G is OK now. so change the default brpc_max_body_size to 6G.

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[Thearas]

Thank you for your contribution to Apache Doris.
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Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
2. Which behaviors were modified. What was the previous behavior, what is it now, why was it modified, and what possible impacts might there be.
3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[dataroaring]

LGTM

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.

[liaoxin01]

LGTM

[GoGoWen]

run buildall

[doris-robot]

TPC-H: Total hot run time: 34129 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpch-tools
Tpch sf100 test result on commit a2882e11377cf3fc759f081d1bf4611280453e13, data reload: false

------ Round 1 ----------------------------------
q1	17629	5233	5134	5134
q2	1938	313	189	189
q3	10353	1339	720	720
q4	10245	1001	515	515
q5	7600	2680	2297	2297
q6	185	165	133	133
q7	906	729	605	605
q8	9306	1288	1079	1079
q9	6843	5133	5100	5100
q10	6883	2362	1963	1963
q11	495	288	270	270
q12	344	351	226	226
q13	17762	3658	3084	3084
q14	228	220	213	213
q15	560	483	474	474
q16	434	427	374	374
q17	605	858	356	356
q18	7817	7367	7247	7247
q19	1713	954	555	555
q20	332	333	221	221
q21	3843	3190	2394	2394
q22	1021	1019	980	980
Total cold run time: 107042 ms
Total hot run time: 34129 ms

----- Round 2, with runtime_filter_mode=off -----
q1	5161	5131	5140	5131
q2	240	326	224	224
q3	2193	2693	2312	2312
q4	1377	1765	1370	1370
q5	4232	4143	4346	4143
q6	212	172	132	132
q7	1975	1936	1736	1736
q8	2593	2542	2585	2542
q9	7111	7224	7092	7092
q10	3077	3275	2853	2853
q11	573	505	480	480
q12	705	774	636	636
q13	3567	3907	3267	3267
q14	291	297	281	281
q15	528	492	484	484
q16	440	477	440	440
q17	1147	1505	1364	1364
q18	7400	7235	7015	7015
q19	796	777	873	777
q20	1931	1943	1830	1830
q21	4808	4347	4287	4287
q22	1096	1022	992	992
Total cold run time: 51453 ms
Total hot run time: 49388 ms

[doris-robot]

TPC-DS: Total hot run time: 186008 ms

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/tpcds-tools
TPC-DS sf100 test result on commit a2882e11377cf3fc759f081d1bf4611280453e13, data reload: false

query1	986	387	389	387
query2	6543	1854	1915	1854
query3	6739	226	229	226
query4	26638	23843	22982	22982
query5	4354	648	469	469
query6	312	218	215	215
query7	4619	508	295	295
query8	286	228	219	219
query9	8644	2639	2644	2639
query10	491	354	290	290
query11	15704	15124	14889	14889
query12	164	107	104	104
query13	1663	532	434	434
query14	9800	6381	6336	6336
query15	207	196	175	175
query16	7578	657	452	452
query17	1169	705	569	569
query18	1990	425	303	303
query19	193	179	162	162
query20	122	123	114	114
query21	211	137	111	111
query22	3940	4232	3844	3844
query23	34346	33089	33113	33089
query24	8366	2405	2412	2405
query25	521	451	398	398
query26	723	270	152	152
query27	2698	511	349	349
query28	4209	2136	2107	2107
query29	654	568	434	434
query30	289	233	197	197
query31	935	866	787	787
query32	71	69	65	65
query33	554	363	323	323
query34	824	853	532	532
query35	801	823	737	737
query36	975	1007	921	921
query37	119	103	75	75
query38	4169	4173	4016	4016
query39	1487	1442	1419	1419
query40	213	123	105	105
query41	65	60	60	60
query42	131	114	113	113
query43	540	537	480	480
query44	1376	830	861	830
query45	187	185	176	176
query46	888	1071	632	632
query47	1744	1793	1720	1720
query48	386	432	327	327
query49	704	482	403	403
query50	648	673	421	421
query51	4153	4177	4093	4093
query52	116	117	105	105
query53	231	260	185	185
query54	584	573	504	504
query55	85	99	86	86
query56	342	311	312	311
query57	1149	1202	1139	1139
query58	272	260	259	259
query59	2694	2758	2671	2671
query60	328	331	319	319
query61	133	122	127	122
query62	801	731	651	651
query63	233	192	192	192
query64	3063	1032	660	660
query65	4368	4224	4199	4199
query66	903	411	303	303
query67	15721	15645	15406	15406
query68	7800	883	525	525
query69	481	299	275	275
query70	1242	1130	1110	1110
query71	441	336	312	312
query72	5642	4805	4971	4805
query73	692	668	354	354
query74	9221	9258	8671	8671
query75	3462	3232	2729	2729
query76	3235	1191	766	766
query77	720	386	289	289
query78	9964	10136	9273	9273
query79	2043	834	595	595
query80	608	508	471	471
query81	473	266	227	227
query82	402	134	104	104
query83	250	255	241	241
query84	247	103	101	101
query85	813	355	322	322
query86	332	315	312	312
query87	4456	4371	4443	4371
query88	3752	2348	2330	2330
query89	387	332	304	304
query90	1961	220	218	218
query91	141	141	110	110
query92	73	63	59	59
query93	1350	952	584	584
query94	681	403	318	318
query95	399	313	308	308
query96	500	569	279	279
query97	2691	2752	2615	2615
query98	241	222	211	211
query99	1332	1428	1272	1272
Total cold run time: 272184 ms
Total hot run time: 186008 ms

[doris-robot]

ClickBench: Total hot run time: 29.49 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit a2882e11377cf3fc759f081d1bf4611280453e13, data reload: false

query1	0.04	0.04	0.03
query2	0.07	0.04	0.03
query3	0.22	0.07	0.07
query4	1.62	0.10	0.10
query5	0.44	0.42	0.42
query6	1.18	0.65	0.67
query7	0.03	0.01	0.02
query8	0.04	0.04	0.04
query9	0.57	0.50	0.52
query10	0.56	0.56	0.57
query11	0.16	0.10	0.11
query12	0.14	0.11	0.11
query13	0.63	0.62	0.60
query14	0.80	0.83	0.82
query15	0.89	0.86	0.87
query16	0.38	0.38	0.39
query17	1.04	1.08	1.06
query18	0.22	0.20	0.21
query19	1.91	1.82	1.83
query20	0.01	0.01	0.01
query21	15.39	0.92	0.55
query22	0.75	1.16	0.76
query23	14.81	1.37	0.63
query24	7.25	1.44	0.66
query25	0.49	0.13	0.20
query26	0.62	0.17	0.13
query27	0.06	0.05	0.06
query28	9.47	0.91	0.46
query29	12.54	4.04	3.32
query30	0.25	0.09	0.06
query31	2.82	0.61	0.39
query32	3.24	0.56	0.48
query33	3.15	3.08	3.13
query34	16.09	5.37	4.82
query35	4.78	4.81	4.78
query36	0.68	0.50	0.49
query37	0.09	0.07	0.06
query38	0.05	0.04	0.04
query39	0.03	0.02	0.03
query40	0.17	0.15	0.14
query41	0.08	0.02	0.02
query42	0.04	0.02	0.03
query43	0.04	0.03	0.03
Total cold run time: 103.84 s
Total hot run time: 29.49 s