chore: [release-3.2.x] fix: Add additional validation for timeout while retrieving headers

[loki-gh-app]

Backport 8322e51 from #14217

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What this PR does / why we need it:
Go 1.23 changed the type of error being returned in the case of a timeout while waiting for headers, as documented in this issue
Which issue(s) this PR fixes:
Fixes #14206

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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