Clarify replica quorum write error message

[Rohithmatham12]

What this changes

• Rewords the write quorum error emitted from pkg/ring/batch.go when enough replicas return the same error family.
• Keeps the same wrapping behavior and address/state/zone context.
• Updates the nearby comment to describe the condition in operator-facing terms instead of the internal maxFailure variable name.

Fixes #5732.

Testing

• GOCACHE=/private/tmp/cortex-go-cache GOMODCACHE=/private/tmp/cortex-go-mod-cache go test ./pkg/ring
• git diff --check