[release-19.0] projection: Return correct collation information (#15801)

[vitess-bot]

Description

This is a backport of #15801

[vitess-bot]

Review Checklist

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General

• Ensure that the Pull Request has a descriptive title.
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Backward compatibility

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.45%. Comparing base (e04b73c) to head (f95a450).

Additional details and impacted files

@@               Coverage Diff                @@
##           release-19.0   #15804      +/-   ##
================================================
- Coverage         67.45%   67.45%   -0.01%     
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  Files              1560     1560              
  Lines            192777   192780       +3     
================================================
- Hits             130041   130038       -3     
- Misses            62736    62742       +6     

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