Respect Straight Join in Vitess query planning

[GuptaManan100]

Description

This PR adds the feature requested in #15527.

After these changes, Vitess respects the order of tables specified in queries using straight joins.

Related Issue(s)

• Fixes Feature Request: Respect Straight Join in Vitess query planning #15527

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.
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Backward compatibility

• Protobuf changes should be wire-compatible.
• Changes to _vt tables and RPCs need to be backward compatible.
• 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.

[systay]

Unfortunately, straight_join no longer produces a warning, and we don't have reliable ways of getting warnings from the planner without turning off schema tracking

[codecov]

Codecov Report

Attention: Patch coverage is 89.41176% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 65.74%. Comparing base (d20f3c5) to head (50425a2).
Report is 6 commits behind head on main.

Files	Patch %	Lines
go/vt/vtgate/planbuilder/operators/join.go	82.85%	6 Missing ⚠️
go/vt/vtgate/planbuilder/operators/apply_join.go	50.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15528      +/-   ##
==========================================
+ Coverage   65.71%   65.74%   +0.03%     
==========================================
  Files        1560     1560              
  Lines      194484   194562      +78     
==========================================
+ Hits       127798   127916     +118     
+ Misses      66686    66646      -40     

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