[release-19.0] Support passing filters to discovery.NewHealthCheck(...) (#16170)

[timvaillancourt]

Description

This PR is a manual backport of #16170 to release-19.0 (as discussed offline with @deepthi)

The reasoning for this backport is it resolves a regression in the txthrottler (in vttablet) that causes a healthcheck stream to be opened to N x tablets (every tablet in every cell), when only the local shard tablets are required. This regression began in v15 when go/vt/discovery was refactored

Related Issue(s)

#16170

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]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

• Ensure that the Pull Request has a descriptive title.
• Ensure there is a link to an issue (except for internal cleanup and flaky test fixes), new features should have an RFC that documents use cases and test cases.

Tests

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• vtctl command output order should be stable and awk-able.

[codecov]

Codecov Report

Attention: Patch coverage is 56.86275% with 22 lines in your changes missing coverage. Please review.

Project coverage is 67.39%. Comparing base (15a1d99) to head (74dfc93).
Report is 1 commits behind head on release-19.0.

Files with missing lines	Patch %	Lines
.../vttablet/tabletserver/txthrottler/tx_throttler.go	57.14%	12 Missing ⚠️
go/vt/discovery/topology_watcher.go	0.00%	5 Missing ⚠️
go/vt/vtgate/tabletgateway.go	0.00%	4 Missing ⚠️
go/vt/throttler/demo/throttler_demo.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff                @@
##           release-19.0   #16871      +/-   ##
================================================
+ Coverage         67.37%   67.39%   +0.02%     
================================================
  Files              1560     1560              
  Lines            193297   193316      +19     
================================================
+ Hits             130229   130291      +62     
+ Misses            63068    63025      -43     

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