[SCB-2841]zone-aware filter support configure group size ratio

[liubao68]

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[codecov-commenter]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (176dc2f) 44.25% compared to head (842f173) 44.29%.
Report is 1 commits behind head on master.

❗ Current head 842f173 differs from pull request most recent head c6c688e. Consider uploading reports for the commit c6c688e to get more accurate results

Files	Patch %	Lines
...b/loadbalance/filter/ZoneAwareDiscoveryFilter.java	72.72%	0 Missing and 3 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #4107      +/-   ##
============================================
+ Coverage     44.25%   44.29%   +0.04%     
- Complexity     5366     5375       +9     
============================================
  Files          1382     1382              
  Lines         34255    34263       +8     
  Branches       3314     3315       +1     
============================================
+ Hits          15158    15176      +18     
+ Misses        17869    17859      -10     
  Partials       1228     1228              

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