Merge branch 'sherlock-ignore-cache' into 'master'

Ignore SQL CACHE hits in Sherlock

See merge request gitlab-org/gitlab-ce!15182

lib/gitlab/sherlock/transaction.rb

@@ -89,7 +89,9 @@ module Gitlab
         ActiveSupport::Notifications.subscribe('sql.active_record') do |_, start, finish, _, data|
           next unless same_thread?
 
-          track_query(data[:sql].strip, data[:binds], start, finish)
+          unless data.fetch(:cached, data[:name] == 'CACHE')
+            track_query(data[:sql].strip, data[:binds], start, finish)
+          end
         end
       end