fix: emit QueryExecutionsByTable for success cases only

[harshit-gangal]

Description

This PR stops emitting QueryExecutionsByTable metrics on error cases.

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
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 67.49%. Comparing base (1c5ca23) to head (3a5a62d).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #18584      +/-   ##
==========================================
- Coverage   67.52%   67.49%   -0.03%     
==========================================
  Files        1607     1607              
  Lines      263324   263325       +1     
==========================================
- Hits       177803   177737      -66     
- Misses      85521    85588      +67     

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[systay]

very nit-picking.

Suggested change

	ctx := context.Background()
	ctx := t.Context()