add gRPC service for querier-to-querier communication #7008
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What this PR does:
This PR implements a querier-to-querier gRPC service enabling direct communication between queriers for distributed execution. The service allows queriers to exchange partial results based on query dependencies
Which issue(s) this PR fixes:
related to distributed query execution proposal #6789
Checklist
CHANGELOG.mdupdated - the order of entries should be[CHANGE],[FEATURE],[ENHANCEMENT],[BUGFIX]