[MINOR][IMPROVEMENT] Return index-file size of n*SEGMENT_SIZE in HDFS reading

[zuston]

What changes were proposed in this pull request?

Return index-file size of n*SEGMENT_SIZE in HDFS reading

Why are the changes needed?

It should keep consistent with the logic of returning the complete index data in localfile reader that data size is always n*SEGMENT_SIZE.

Does this PR introduce any user-facing change?

No

How was this patch tested?

[codecov-commenter]

Codecov Report

Merging #204 (1cfe418) into master (9b83f66) will increase coverage by 0.03%.
The diff coverage is 76.92%.

@@             Coverage Diff              @@
##             master     #204      +/-   ##
============================================
+ Coverage     59.02%   59.06%   +0.03%     
- Complexity     1326     1327       +1     
============================================
  Files           160      160              
  Lines          8699     8708       +9     
  Branches        815      817       +2     
============================================
+ Hits           5135     5143       +8     
+ Misses         3301     3300       -1     
- Partials        263      265       +2     

Impacted Files	Coverage Δ
.../storage/handler/impl/HdfsShuffleWriteHandler.java	85.07% <ø> (ø)
...orage/handler/impl/LocalFileServerReadHandler.java	77.96% <50.00%> (-2.40%)	⬇️
...e/storage/handler/impl/HdfsShuffleReadHandler.java	57.14% <87.50%> (+6.12%)	⬆️
.../java/org/apache/uniffle/common/util/RssUtils.java	69.32% <100.00%> (-0.80%)	⬇️
.../apache/uniffle/common/exception/RssException.java	100.00% <0.00%> (+50.00%)	⬆️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[zuston]

PTAL @jerqi . If OK, I will add some UTs.

[jerqi]

PTAL @jerqi . If OK, I will add some UTs.

You can go ahead.

[jerqi]

LGTM, thanks @zuston