Refactor issue boards switcher to single file Vue component (CE-port) (!23274) · Merge requests · GitLab.org / GitLab FOSS · GitLab

What does this MR do?

CE-port of https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/8519

What are the relevant issue numbers?

part of https://gitlab.com/gitlab-org/gitlab-ee/issues/7715

Does this MR meet the acceptance criteria?

Changelog entry added, if necessary
Documentation created/updated
Tests added for this feature/bug
Conforms to the code review guidelines
Conforms to the merge request performance guidelines
Conforms to the style guides
Conforms to the database guides
Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.