Move todos button in shared component

...javascripts/work_items/components/shared/todos_toggle.vue

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

...scripts/work_items/components/work_item_sticky_header.vue

app/assets/javascripts/work_items/graphql/cache_utils.js

...rontend/work_items/components/shared/todos_toggle_spec.js

spec/frontend/work_items/components/work_item_detail_spec.js

...end/work_items/components/work_item_sticky_header_spec.js