Performance bar shows queries that hit the cache
https://gitlab.com/gitlab-org/gitlab-ce/blob/master/lib/gitlab/performance_bar/peek_query_tracker.rb intends to remove cached queries, but according to https://gitlab.com/gitlab-org/gitlab-ce/issues/43114#note_63661914 and https://gitlab.com/gitlab-org/gitlab-ce/snippets/1705110, that is not the case.