Switched store-gateway query concurrency limit from per-tenant to shared #2797
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What this PR does:
The store-gateway currently has a per-tenant query concurrency limit, but it's not much useful in a multi-tenant cluster because what we really want to protect is from the concurrent number of queries in a store-gateway instance. I've done this change into Thanos first and then in this PR I'm switching the limit from per-tenant to a shared one.
Which issue(s) this PR fixes:
N/A
Checklist
CHANGELOG.mdupdated - the order of entries should be[CHANGE],[FEATURE],[ENHANCEMENT],[BUGFIX]