Make tablet collation mismatch warning throttled

[vmg]

Description

This is a backport from an internal PR by @aquarapid. The warning which we emit when there's a mismatch between Vitess' collations and the collations in the MySQL cluster can get real noisy because it's emitted once per query. Throttle it with the log throttler.

Related Issue(s)

• Throttle tablet collation mismatch warnings #15187

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

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[codecov]

Codecov Report

Attention: 146 lines in your changes are missing coverage. Please review.

Comparison is base (eddb39e) 47.29% compared to head (0166c89) 70.63%.
Report is 97 commits behind head on main.

Files	Patch %	Lines
go/vt/mysqlctl/builtinbackupengine.go	12.90%	54 Missing ⚠️
go/vt/mysqlctl/backupengine.go	0.00%	20 Missing ⚠️
go/vt/mysqlctl/xtrabackupengine.go	0.00%	15 Missing ⚠️
go/vt/topo/keyspace.go	78.72%	10 Missing ⚠️
go/mysql/conn.go	53.84%	6 Missing ⚠️
go/vt/schemadiff/column.go	25.00%	6 Missing ⚠️
go/vt/mysqlctl/backup.go	37.50%	5 Missing ⚠️
go/mysql/capabilities/capability.go	91.48%	4 Missing ⚠️
go/mysql/query.go	77.77%	4 Missing ⚠️
go/vt/mysqlctl/schema.go	72.72%	3 Missing ⚠️
... and 14 more

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #15123       +/-   ##
===========================================
+ Coverage   47.29%   70.63%   +23.33%     
===========================================
  Files        1137     1375      +238     
  Lines      238684   182225    -56459     
===========================================
+ Hits       112895   128713    +15818     
+ Misses     117168    53512    -63656     
+ Partials     8621        0     -8621     

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