fix: remove usage of unsafe string in label adapter unmarshal

[ashwanthgoli]

What this PR does / why we need it:

Unmarshal method of LabelAdapter was using yoloString to reference parts of a bytes buffer alloced by grpc lib.
But with release 1.66.0, grpc introduces a new codec that reuses buffers. Referencing parts of these buffers is not safe anymore since these bytes could get cleared or replaced by other messages.

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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[na--]

This should close #14053