Merge branch 'psi-work-item-state' into 'master'

app/assets/javascripts/work_items/components/item_state.vue

...ts/javascripts/work_items/components/work_item_detail.vue

...ets/javascripts/work_items/components/work_item_state.vue

app/assets/javascripts/work_items/constants.js

...javascripts/work_items/graphql/work_item.fragment.graphql

app/assets/javascripts/work_items/pages/create_work_item.vue

spec/frontend/work_items/components/item_state_spec.js

spec/frontend/work_items/components/work_item_state_spec.js

spec/frontend/work_items/mock_data.js