fix: scheduling constraints (backport k239)

[loki-gh-app]

Backport b45a31e from #16045

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What this PR does / why we need it:

Makes the scheduling constraint more flexible / gives more options to satisfy what we need for our AWS clusters.

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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