Update Planning for Limits in the presence of foreign keys

[GuptaManan100]

Description

This PR adds support for UPDATE queries with the limit clause in the presence of foreign keys.

Related Issue(s)

• RFC: Foreign Key Support in Vitess #12967

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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Documentation

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Backward compatibility

• Protobuf changes should be wire-compatible.
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• RPC changes should be compatible with vitess-operator
• If a flag is removed, then it should also be removed from vitess-operator and arewefastyet, if used there.
• vtctl command output order should be stable and awk-able.

[codecov]

Codecov Report

Attention: Patch coverage is 95.74468% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 65.45%. Comparing base (236f84c) to head (dd69bb3).
Report is 6 commits behind head on main.

Files	Patch %	Lines
go/vt/vtgate/planbuilder/operators/update.go	95.74%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15372      +/-   ##
==========================================
+ Coverage   65.42%   65.45%   +0.03%     
==========================================
  Files        1561     1562       +1     
  Lines      193630   193951     +321     
==========================================
+ Hits       126674   126948     +274     
- Misses      66956    67003      +47     

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