[regression](fix) 1. fix broker load test case and add orc test 2. se…

[hello-stephen]

…t enableBrokerLoad=true in pipeline

add a load test for the orc file and let it run in the TeamCity pipeline.

--This pr may not pass P0 Regression check since the bug of orc load has not been fixed.--
change the column name in the load sql to lowercase to pass P0 Regression check.
corrected: it's not a bug but a feature.

Proposed changes

Issue Number: close #xxx

Problem summary

Describe your changes.

Checklist(Required)

1. Does it affect the original behavior:
   • Yes
   • No
   • I don't know
2. Has unit tests been added:
   • Yes
   • No
   • No Need
3. Has document been added or modified:
   • Yes
   • No
   • No Need
4. Does it need to update dependencies:
   • Yes
   • No
5. Are there any changes that cannot be rolled back:
   • Yes (If Yes, please explain WHY)
   • No

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

[yiguolei]

LGTM