Add ability to change member role to role details drawer

...ts/javascripts/members/components/table/members_table.vue

...ascripts/members/components/table/role_details_drawer.vue

...ts/javascripts/members/components/table/role_selector.vue

app/assets/javascripts/members/utils.js

ee/app/assets/javascripts/members/utils.js

ee/spec/frontend/members/components/table/max_role_spec.js

...tend/members/components/table/role_details_drawer_spec.js

...c/frontend/members/components/table/role_selector_spec.js

ee/spec/frontend/members/mock_data.js

ee/spec/frontend/members/utils_spec.js

locale/gitlab.pot

spec/frontend/members/components/table/members_table_spec.js

...tend/members/components/table/role_details_drawer_spec.js

spec/frontend/members/components/table/role_selector_spec.js

spec/frontend/members/mock_data.js

spec/frontend/members/utils_spec.js