Migrate `app/assets/javascripts/projects/commit/store/index.js` to Pinia
[`app/assets/javascripts/projects/commit/store/index.js`](https://gitlab.com/gitlab-org/gitlab/blob/3e60bba206715737ac53d6e50fea4b76a425b6d6/app/assets/javascripts/projects/commit/store/index.js) store should be migrated to Pinia using [the single-step migration](https://docs.gitlab.com/development/fe_guide/pinia/#single-step-migration).
Files to cover (non-exhaustive):
- `app/assets/javascripts/projects/commit/store/index.js`
- `app/assets/javascripts/projects/commit/store/actions.js`
- `app/assets/javascripts/projects/commit/store/getters.js`
- `app/assets/javascripts/projects/commit/store/mutations.js`
- `app/assets/javascripts/projects/commit/store/state.js`
- `app/assets/javascripts/projects/commit/init_cherry_pick_commit_modal.js`
- `app/assets/javascripts/projects/commit/init_revert_commit_modal.js`
- `app/assets/javascripts/projects/commit/components/projects_dropdown.vue`
- `app/assets/javascripts/projects/commit/components/branches_dropdown.vue`
- `app/assets/javascripts/projects/commit/components/form_modal.vue`
And their respective specs.
issue