fix: Fixes pattern pruning stability

[cyriltovena]

What this PR does / why we need it:

This fixes pattern query result instability. This was mostly due to re-using drain which uses a LRU cache.

The PR also relax the ring querying as best effort instead of enforcing all replicas to be alive.

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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