Merge branch '300973-add-external-approvals-to-projects' into 'master'

...s/javascripts/approvals/components/approval_gate_icon.vue

...javascripts/approvals/components/approver_type_select.vue

...ts/javascripts/approvals/components/modal_rule_remove.vue

...s/approvals/components/project_settings/project_rules.vue

ee/app/assets/javascripts/approvals/components/rule_form.vue

ee/app/assets/javascripts/approvals/constants.js

ee/app/assets/javascripts/approvals/mappers.js

ee/app/controllers/ee/projects_controller.rb

...eatures/projects/settings/merge_requests_settings_spec.rb

...s/components/__snapshots__/modal_rule_remove_spec.js.snap

.../frontend/approvals/components/approval_gate_icon_spec.js

...rontend/approvals/components/approver_type_select_spec.js

...c/frontend/approvals/components/modal_rule_remove_spec.js

...provals/components/project_settings/project_rules_spec.js

ee/spec/frontend/approvals/components/rule_form_spec.js

ee/spec/frontend/approvals/mocks.js

locale/gitlab.pot