[SCB-2385]fix IsolationDiscoveryFilter create many temporary objects

[lbc97]

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[codecov-commenter]

Codecov Report

Merging #2731 (f87ee25) into 1.3.x (ad53a38) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head f87ee25 differs from pull request most recent head b075707. Consider uploading reports for the commit b075707 to get more accurate results

@@             Coverage Diff              @@
##              1.3.x    #2731      +/-   ##
============================================
- Coverage     82.99%   82.99%   -0.01%     
  Complexity      746      746              
============================================
  Files          1233     1233              
  Lines         33082    33081       -1     
  Branches       3001     3001              
============================================
- Hits          27458    27457       -1     
  Misses         4438     4438              
  Partials       1186     1186              

Impacted Files	Coverage Δ
...b/loadbalance/filter/IsolationDiscoveryFilter.java	87.01% <100.00%> (-0.17%)	⬇️

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