Instead of calling the bloom store directly on each and every request to filter chunk refs based on the given filters, we want to queue requests in per-tenant queues and process batches of requests that can be multiplexed to avoid excessive seeking in the bloom block queriers when checking chunk matches.
This PR re-uses the request queue implementation used in the query scheduler. To do so, it moves the queue related code from the scheduler into a separate package `pkg/queue` and renames occurrences of "querier" to "consumer" to be more generic.
The bloom gateway instantiates the request queue when starting the service. The gRPC method `FilterChunkRefs` then enqueues incoming requests to that queue.
**Special notes for your reviewer**:
For testing purposes, this PR also contains a dummy implementation of the workers. The worker implementation - which includes multiplexing of multiple tasks - is subject to a separate PR.
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Signed-off-by: Christian Haudum <christian.haudum@gmail.com>
