Merge branch 'hly-graphql-explorer-performance-bar' into 'master'

Add performance bar to GraphQL explorer

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/171948



Merged-by: Lukas Eipert <leipert@gitlab.com>
Approved-by: Mark Florian <mflorian@gitlab.com>
Reviewed-by: Lukas Eipert <leipert@gitlab.com>
Reviewed-by: Mark Florian <mflorian@gitlab.com>
Co-authored-by: Heinrich Lee Yu <heinrich@gitlab.com>