[MINOR][IMPROVEMENT][STORAGE] Fix storage module code style

[roryqi]

What changes were proposed in this pull request?

Solve issue #123, solve storage module code style problems

Why are the changes needed?

Improve our test code style

Does this PR introduce any user-facing change?

No

How was this patch tested?

I add the test code style check commits, storage module passed.
https://github.com/jerqi/incubator-uniffle/runs/7691133341?check_suite_focus=true

[codecov-commenter]

Codecov Report

Merging #131 (2046028) into master (fce4bb6) will increase coverage by 0.01%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #131      +/-   ##
============================================
+ Coverage     57.17%   57.18%   +0.01%     
  Complexity     1201     1201              
============================================
  Files           150      150              
  Lines          8177     8179       +2     
  Branches        773      773              
============================================
+ Hits           4675     4677       +2     
+ Misses         3257     3256       -1     
- Partials        245      246       +1     

Impacted Files	Coverage Δ
.../apache/uniffle/coordinator/ClientConfManager.java	91.54% <0.00%> (-1.41%)	⬇️
...ava/org/apache/uniffle/common/web/JettyServer.java	56.25% <0.00%> (-0.68%)	⬇️
...he/uniffle/server/storage/LocalStorageManager.java	61.53% <0.00%> (-0.37%)	⬇️
.../org/apache/uniffle/common/config/RssBaseConf.java	91.86% <0.00%> (+0.06%)	⬆️
...org/apache/uniffle/server/ShuffleFlushManager.java	78.53% <0.00%> (+0.12%)	⬆️
...a/org/apache/uniffle/server/RegisterHeartBeat.java	44.64% <0.00%> (+2.05%)	⬆️
...va/org/apache/uniffle/common/util/ThreadUtils.java	50.00% <0.00%> (+50.00%)	⬆️

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