Remove JSON annotations

[systay]

Description

Very small PR that just removes unnecessary JSON annotations on a few types.

Related Issue(s)

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
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• Tests were added or are not required
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• Documentation was added or is not required

[vitess-bot]

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[frouioui]

What's the main reason why we want to remove these?

Approving to unblock.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.68%. Comparing base (485d736) to head (56fa677).

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #16437   +/-   ##
=======================================
  Coverage   68.67%   68.68%           
=======================================
  Files        1548     1548           
  Lines      199124   199124           
=======================================
+ Hits       136745   136760   +15     
+ Misses      62379    62364   -15     

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[systay]

What's the main reason why we want to remove these?

They are unnecessary. We don't need them. So it's better to remove.
These fields are sometimes empty, but we never turn them into JSON.