* Updates the instrumentation_server service to use mux instead of the builtin router, and have it store the router in the module server: this is so we can register the /ring endpoint to check the status of the ring
* Create a new Ring service that depends on the instrumentation server and declares it as a dependency for the storage server
* Create standalone MemberlistKV service for Ring service to use
* Update the storage server Search and GetStats handler to distribute requests if applicable
* Storage server runs own instrumentation server if its the sole target. Starts adding some sample metrics for now.
* adds metric for failed optimistic locks
* refactors metrics registration to own method on service for testability. Adds tests.
* Register sql storage server metrics from within the service
* fixes test
* troubleshooting drone test failures. Maybe timing when starting instrumentation server?
* Waits until instrumentation server has started. Updates tests.
* defer wont get called unless theres an error. removing.
* wait for instrumentation server to be running
* linter - close res body
* use port 3000 for metrics and removes test metric inc() call
* fixes test - updates port
* refactors module server to provide an instrumentation server module when there is no ALL or CORE target provided and running as single target
* make instrumentation server a dependency of all modules that do not run their own http server
* adds module server test
* adds tests for instrumentation service and removes old tests that aren't needed
* ignore error in test
* uses helper to start and run service
* when running wait on ctx done or http server err
* wait for http server
* removes println
* updates module server test to be integration test
* require no error in goroutine
* skips integration test when GRAFANA_TEST_DB not defined
* move http server start into start, verify returned content
* make test error when run fails
* try waiting longer and see if drone tests pass
* update integration test mysql creds to match drone
* go back to only waiting half second
* debug log drone mysql connection string
* use same db connection config as drone
* try using same hostname as drone
* cant use localhost as mysql hostname in drone tests. Need to parse it from the cfg db connection string
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Co-authored-by: Dan Cech <dcech@grafana.com>
