optimize: optimize the reload during startup in file mode

[wangliang181230]

Ⅰ. Describe what this PR did

optimize: opt the reload during startup in file mode.
优化TC的文件模式，在启动过程中重载文件到内存中的操作。

避免因为一些已完成的全局事务数据堆积太多，导致启动过程中内存溢出了。

Ⅱ. Does this pull request fix one issue?

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[codecov-io]

Codecov Report

Merging #3215 (cdb9b4f) into develop (23a407e) will decrease coverage by 0.10%.
The diff coverage is 42.22%.

@@              Coverage Diff              @@
##             develop    #3215      +/-   ##
=============================================
- Coverage      51.11%   51.00%   -0.11%     
+ Complexity      3297     3257      -40     
=============================================
  Files            614      609       -5     
  Lines          20125    20044      -81     
  Branches        2514     2507       -7     
=============================================
- Hits           10287    10224      -63     
+ Misses          8806     8798       -8     
+ Partials        1032     1022      -10     

Impacted Files	Coverage Δ	Complexity Δ
...erver/storage/file/session/FileSessionManager.java	56.93% <42.22%> (-4.74%)	27.00 <3.00> (ø)
.../src/main/java/io/seata/core/rpc/ShutdownHook.java	0.00% <0.00%> (-82.86%)	0.00% <0.00%> (-8.00%)
...c/main/java/io/seata/config/FileConfiguration.java	41.77% <0.00%> (-1.53%)	11.00% <0.00%> (ø%)
...in/java/io/seata/server/session/GlobalSession.java	82.72% <0.00%> (-0.91%)	70.00% <0.00%> (-1.00%)
...ver/storage/db/session/DataBaseSessionManager.java	36.20% <0.00%> (-0.64%)	12.00% <0.00%> (ø%)
...ver/storage/redis/session/RedisSessionManager.java	29.31% <0.00%> (-0.52%)	10.00% <0.00%> (ø%)
.../java/io/seata/core/compressor/CompressorType.java	0.00% <0.00%> (ø)	0.00% <0.00%> (ø%)
...in/java/io/seata/rm/datasource/sql/struct/Row.java	100.00% <0.00%> (ø)	10.00% <0.00%> (ø%)
...n/java/io/seata/rm/datasource/undo/SQLUndoLog.java	77.77% <0.00%> (ø)	10.00% <0.00%> (ø%)
.../java/io/seata/rm/datasource/sql/struct/Field.java	90.90% <0.00%> (ø)	9.00% <0.00%> (ø%)
... and 21 more

[slievrly]

LGTM

[xingfudeshi]

LGTM.

[funky-eyes]

LGTM