[#1711] feat(server): introduce the reconfigurable conf

[zuston]

What changes were proposed in this pull request?

(Please outline the changes and how this PR fixes the issue.)

Why are the changes needed?

(Please clarify why the changes are needed. For instance,

1. If you propose a new API, clarify the use case for a new API.
2. If you fix a bug, describe the bug.)

Fix: # (issue)

Does this PR introduce any user-facing change?

(Please list the user-facing changes introduced by your change, including

1. Change in user-facing APIs.
2. Addition or removal of property keys.)

No.

How was this patch tested?

(Please test your changes, and provide instructions on how to test it:

1. If you add a feature or fix a bug, add a test to cover your changes.
2. If you fix a flaky test, repeat it for many times to prove it works.)

[zuston]

I drafted this impl, please take a look. @jerqi

[github-actions[bot]]

Test Results

 2 419 files  +28   2 419 suites  +28   4h 58m 9s :stopwatch: + 1m 23s    933 tests + 5     932 :white_check_mark: + 5   1 :zzz: ±0  0 :x: ±0  10 819 runs  +65  10 805 :white_check_mark: +65  14 :zzz: ±0  0 :x: ±0 

Results for commit 0bdfdeb1. ± Comparison against base commit d4a5fb75.

:recycle: This comment has been updated with latest results.

[zuston]

I drafted this impl, please take a look. @jerqi

gentle ping @jerqi

[zuston]

I drafted this impl, please take a look. @jerqi

gentle ping @jerqi

ping again

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 66.25000% with 27 lines in your changes are missing coverage. Please review.

Project coverage is 54.13%. Comparing base (6f6d35a) to head (ce5230a). Report is 27 commits behind head on master.

Files	Patch %	Lines
...ache/uniffle/common/ReconfigurableConfManager.java	65.78%	24 Missing and 2 partials :warning:
.../java/org/apache/uniffle/server/ShuffleServer.java	0.00%	1 Missing :warning:

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #1712      +/-   ##
============================================
- Coverage     54.86%   54.13%   -0.74%     
- Complexity     2358     2928     +570     
============================================
  Files           368      432      +64     
  Lines         16379    23398    +7019     
  Branches       1504     2186     +682     
============================================
+ Hits           8986    12666    +3680     
- Misses         6862     9958    +3096     
- Partials        531      774     +243     

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[zuston]

Merged. Thanks @jerqi review