revert: "perf: Reduce allocations for JSON and logfmt parser (#18637)"

[poyzannur]

This reverts commit adb27ff.

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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