Merge branch...

Merge branch '434169-implement-search-mechanism-for-work-item-epic-in-legacy-issue-s-sidebar' into 'master' 

Enable search mechanism if work item epic are shown in issue sidebar

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/144737



Merged-by: Florie Guibert <fguibert@gitlab.com>
Approved-by: Serena Fang <sfang@gitlab.com>
Approved-by: Florie Guibert <fguibert@gitlab.com>
Approved-by: Elwyn Benson <ebenson@gitlab.com>
Co-authored-by: Rajan Mistry <rmistry@gitlab.com>