Merge branch...

Merge branch '390778-allow-branch-dropdowns-to-expand-to-fit-the-width-of-the-screen-if-there-is-space' into 'master' 

Allow Graph branch dropdown to expand to fit the width of the screen

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/151995



Merged-by: Stanislav Lashmanov <slashmanov@gitlab.com>
Approved-by: Michael Le <mle@gitlab.com>
Approved-by: Rajan Mistry <rmistry@gitlab.com>
Approved-by: Stanislav Lashmanov <slashmanov@gitlab.com>
Co-authored-by: Ishmeet <singhishmeet16@gmail.com>