optimize: optimize ConsistentHashLoadBalance Algorithm

[slievrly]

• I have registered the PR changes.

Ⅰ. Describe what this PR did

optimize ConsistentHashLoadBalance Algorithm

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]

Codecov Report

Attention: Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.

Please upload report for BASE (2.x@595277d). Learn more about missing BASE report.

Files	Patch %	Lines
...scovery/loadbalance/ConsistentHashLoadBalance.java	90.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@          Coverage Diff           @@
##             2.x    #6748   +/-   ##
======================================
  Coverage       ?   50.87%           
  Complexity     ?     5915           
======================================
  Files          ?     1058           
  Lines          ?    36779           
  Branches       ?     4369           
======================================
  Hits           ?    18712           
  Misses         ?    16177           
  Partials       ?     1890           

Files	Coverage Δ
...scovery/loadbalance/ConsistentHashLoadBalance.java	85.71% <90.00%> (ø)

[funky-eyes]

LGTM