Add vuex store for registry settings

- actions
- mutations

Add vue app for registry settings and load it

 - app
- bundle file
- load bundle in index
Add tests for vue and vuex registry settings

- main app
- actions
- mutations

Add partial to load vue app

Add new section to CI/CD settings

- add feature flag
- add header as haml
- load partial for vue app

Update translations strings

Add helper and vuex to test file

Apply suggestion to registry_settings_app_spec.js

Apply suggestion to ci_cd/show.html.haml
Apply suggestion to registry_settings_app.vue
Update snapshot with new copy