Fix: Update found rows pool transaction capacity dynamically via vttablet debug/env

[harshit-gangal]

Description

This PR fixes a bug in debug/env to also update both normal and found rows pool of Transaction Pool when modified through /debug/env UI of vttablet.

Related Issue(s)

• Feature Request: Support dynamically adjusting the number of transaction connection pools and read-only connection pools #17046

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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[codecov]

Codecov Report

Attention: Patch coverage is 60.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 67.43%. Comparing base (a9bab82) to head (43af039).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
go/vt/vttablet/tabletserver/tabletserver.go	60.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17055   +/-   ##
=======================================
  Coverage   67.42%   67.43%           
=======================================
  Files        1569     1569           
  Lines      252120   252124    +4     
=======================================
+ Hits       169997   170015   +18     
+ Misses      82123    82109   -14     

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[harshit-gangal]

#17055 (comment)

If you look at the diff as a whole it will be difficult to follow. I have made individual 6 commits to show the changes made with intention.