Use reusable GitHub Actions for testing

This reduces the duplication between projects. For example, this ensures
testing on Ruby 2.7 which previously didn't happen.

Right now this is incomplete because it loses the caching step that
happens on a push to master.

.github/workflows/ruby_tests.yml

@@ -1,71 +1,19 @@
 name: Ruby Testing
-on:
-  pull_request:
-  push:
-    branches:
-    - master
-env:
-  BUNDLE_WITHOUT: journald:development:console:libvirt
-  RAILS_ENV: test
-  DATABASE_URL: postgresql://postgres:@localhost/test
-  DATABASE_CLEANER_ALLOW_REMOTE_DATABASE_URL: true
+
+on: pull_request
+
+concurrency:
+  group: ${{ github.head_ref }}
+  cancel-in-progress: true
+
 jobs:
   rubocop:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - name: Setup Ruby
-        uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: 2.6
-          bundler-cache: true
-      - name: Run rubocop
-        run: bundle exec rubocop
+    name: Rubocop
+    uses: ekohl/actions/.github/workflows/rubocop.yml@v0
+
   test_ruby:
-    runs-on: ubuntu-latest
+    name: Ruby
     needs: rubocop
-    services:
-      postgres:
-        image: postgres:12.1
-        ports: ['5432:5432']
-        options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
-    strategy:
-      fail-fast: false
-      matrix:
-        foreman-core-branch: [develop]
-        ruby-version: [2.5, 2.6]
-        node-version: [12]
-    steps:
-      - name: Install build packages
-        run: |
-          sudo apt-get update
-          sudo apt-get install build-essential libcurl4-openssl-dev zlib1g-dev libpq-dev
-      - uses: actions/checkout@v2
-        with:
-          repository: theforeman/foreman
-          ref: ${{ matrix.foreman-core-branch }}
-      - uses: actions/checkout@v2
-        with:
-          path: foreman_ansible
-      - name: Setup Bundler
-        run: |
-          echo "gem 'foreman_ansible', path: './foreman_ansible'" > bundler.d/foreman_ansible.local.rb
-      - name: Setup Ruby
-        uses: ruby/setup-ruby@v1
-        with:
-          ruby-version: ${{ matrix.ruby-version }}
-          bundler-cache: true
-      - name: Setup Node
-        if: github.event_name != 'push'
-        uses: actions/setup-node@v1
-        with:
-          node-version:  ${{ matrix.node-version }}
-      - name: Prepare test env
-        if: github.event_name != 'push'
-        run: |
-          bundle exec rake db:create
-          bundle exec rake db:migrate
-      - name: Run plugin tests
-        if: github.event_name != 'push'
-        run: |
-          bundle exec rake test:foreman_ansible
+    uses: ekohl/actions/.github/workflows/foreman_plugin.yml@v0
+    with:
+      plugin: foreman_ansible