[Cherry Pick #30119] [Go SDK] Evict closed readers from the cache.

[lostluck]

Cherry pick of #30119 to fix #28142 in the 2.54.0 release.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9cfc99b) 38.41% compared to head (768e161) 38.41%.

Additional details and impacted files

@@               Coverage Diff               @@
##           release-2.54.0   #30133   +/-   ##
===============================================
  Coverage           38.41%   38.41%           
===============================================
  Files                 697      697           
  Lines              102214   102217    +3     
===============================================
+ Hits                39269    39271    +2     
- Misses              61317    61321    +4     
+ Partials             1628     1625    -3     

Flag	Coverage Δ
go	54.17% <100.00%> (+<0.01%)	⬆️

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