Address Visual follow-ups in boards_selector

Address Visual follow-ups in app/assets/javascripts/boards/components/boards_selector.vue

Based on discussion, some migration follow-ups needs to be addressed in this issue

added Pajamas component:dropdown devopsmanage frontend groupfoundations maintenancerefactor pajamasintegrate sectiondev typemaintenance workflowready for development + 1 deleted label

marked this issue as related to #413021 (closed)

added to epic &10695

mentioned in merge request !129722 (merged)

added severity4 label

added workflowplanning breakdown label and removed workflowready for development label

removed 1 deleted label