Define `tags:` globally for all jobs

Instead of defining `tags:` per-job,
we can use `default:tags:` to clearly
indicate that all jobs use `tags:`

.gitlab-ci.yml

@@ -12,6 +12,11 @@ stages:
   - post-qa
   - pages
 
+# always use `gitlab-org` runners
+default:
+  tags:
+    - gitlab-org
+
 workflow:
   rules:
     # If `$FORCE_GITLAB_CI` is set, create a pipeline.

.gitlab/ci/dev-fixtures.gitlab-ci.yml

 .run-dev-fixtures:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script

.gitlab/ci/docs.gitlab-ci.yml

 .review-docs:
   extends:
-    - .default-tags
     - .default-retry
     - .docs:rules:review-docs
   allow_failure: true
@@ -42,7 +41,6 @@ review-docs-cleanup:
 
 docs lint:
   extends:
-    - .default-tags
     - .default-retry
     - .docs:rules:docs-lint
   image: "registry.gitlab.com/gitlab-org/gitlab-docs:lint"
@@ -64,7 +62,6 @@ docs lint:
 
 graphql-reference-verify:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script

.gitlab/ci/frontend.gitlab-ci.yml

@@ -10,7 +10,6 @@
 
 .gitlab:assets:compile-metadata:
   extends:
-    - .default-tags
     - .default-retry
     - .default-before_script
     - .assets-compile-cache
@@ -64,7 +63,6 @@ gitlab:assets:compile pull-cache:
 
 .compile-assets-metadata:
   extends:
-    - .default-tags
     - .default-retry
     - .default-before_script
     - .assets-compile-cache
@@ -122,7 +120,6 @@ compile-assets pull-cache as-if-foss:
 
 .frontend-fixtures-base:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script
@@ -160,7 +157,6 @@ frontend-fixtures-as-if-foss:
 
 .frontend-job-base:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script
@@ -242,7 +238,6 @@ jest-as-if-foss:
 
 coverage-frontend:
   extends:
-    - .default-tags
     - .default-retry
     - .frontend:rules:default-frontend-jobs
   needs: ["jest"]
@@ -262,7 +257,6 @@ coverage-frontend:
 
 .qa-frontend-node:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .frontend:rules:qa-frontend-node
@@ -290,7 +284,6 @@ qa-frontend-node:latest:
 
 webpack-dev-server:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .frontend:rules:default-frontend-jobs

.gitlab/ci/global.gitlab-ci.yml

-.default-tags:
-  tags:
-    - gitlab-org
-
 .default-retry:
   retry:
     max: 2  # This is confusing but this means "3 runs at max".

.gitlab/ci/memory.gitlab-ci.yml

 .only-code-memory-job-base:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script

.gitlab/ci/pages.gitlab-ci.yml

 pages:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .pages:rules

.gitlab/ci/qa.gitlab-ci.yml

 .qa-job-base:
   extends:
-    - .default-tags
     - .default-retry
   stage: test
   needs: []

.gitlab/ci/rails.gitlab-ci.yml

@@ -7,7 +7,6 @@
 
 .rails-job-base:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script

.gitlab/ci/review.gitlab-ci.yml

 .review-docker:
   extends:
-    - .default-tags
     - .default-retry
   image: registry.gitlab.com/gitlab-org/gitlab-build-images:gitlab-qa-alpine-ruby-2.6
   services:
@@ -29,7 +28,6 @@ build-qa-image:
 
 review-cleanup:
   extends:
-    - .default-tags
     - .default-retry
     - .review:rules:review-cleanup
   stage: prepare
@@ -46,7 +44,6 @@ review-cleanup:
 
 review-build-cng:
   extends:
-    - .default-tags
     - .default-retry
     - .review:rules:mr-and-schedule
   image: ruby:2.6-alpine
@@ -63,7 +60,6 @@ review-build-cng:
 
 .review-workflow-base:
   extends:
-    - .default-tags
     - .default-retry
   image: registry.gitlab.com/gitlab-org/gitlab-build-images:gitlab-charts-build-base
   variables:
@@ -217,7 +213,6 @@ review-performance:
 
 parallel-spec-reports:
   extends:
-    - .default-tags
     - .review:rules:mr-only-manual
   image: ruby:2.6-alpine
   stage: post-qa
@@ -244,7 +239,6 @@ parallel-spec-reports:
 
 danger-review:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .review:rules:danger

.gitlab/ci/setup.gitlab-ci.yml

@@ -2,7 +2,6 @@
 # rubygems.org in the future.
 cache gems:
   extends:
-    - .default-tags
     - .default-retry
     - .default-cache
     - .default-before_script
@@ -21,7 +20,6 @@ cache gems:
 
 .minimal-job:
   extends:
-    - .default-tags
     - .default-retry
   needs: []
 

.gitlab/ci/yaml.gitlab-ci.yml

@@ -2,7 +2,6 @@
 # This uses rules from project root `.yamllint`.
 lint-ci-gitlab:
   extends:
-    - .default-tags
     - .default-retry
     - .yaml:rules
   image: sdesbure/yamllint:latest