subscriptions module is type safe

.gitlab-ci.yml

frontend/@types/v-clipboard/index.d.ts

...c/components/submission_notes/RouteChangeConfirmation.vue

.../src/components/submission_notes/SubmissionCorrection.vue

...tend/src/components/submission_notes/base/CommentForm.vue

.../src/components/submission_notes/base/FeedbackComment.vue

...ssion_notes/toolbars/AnnotatedSubmissionBottomToolbar.vue

...mission_notes/toolbars/ToggleFeedbackVisibilityButton.vue

...end/src/components/subscriptions/SubscriptionCreation.vue

...tend/src/components/subscriptions/SubscriptionForList.vue

...nd/src/components/subscriptions/SubscriptionsForStage.vue

frontend/src/pages/student/StudentSubmissionPage.vue

frontend/src/store/actions.ts

frontend/src/store/modules/submission-notes.ts

frontend/src/store/store.ts

frontend/src/util/helpers.ts