chore: [k204] fix(otel): Map 500 errors to 503

[grafanabot]

Backport b31e04e from #13173

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What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #

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Checklist

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