feat: introduce github actions (#781)

* feat: introduce github actions

* fix: allow 429 status

* fix: clean duplicate urls

* feat: upload results

* fix: clean up more 404s

* feat: reduce delay

.github/workflows/validator.yml

@@ -0,0 +1,56 @@
+name: Validator
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types:
+      - opened
+      - reopened
+      - synchronize
+      
+env:
+  RUBY_VERSION: '2.6'
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  validator:
+    name: Validator
+    runs-on: ubuntu-latest
+    steps:
+    - id: setup-ruby
+      name: Setup Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ env.RUBY_VERSION }}
+
+    - id: checkout
+      name: Checkout
+      uses: actions/checkout@v2
+
+    - id: install-gem
+      name: Install gem
+      run: |
+        gem install awesome_bot
+
+    - id: validate
+      name: Validate
+      run: |
+        awesome_bot README.md --request-delay 0.5 --allow-timeout --allow-redirect
+        
+    - id: upload-artifact
+      name: Upload artifact
+      uses: actions/upload-artifact@v2
+      if: failure()
+      with:
+        if-no-files-found: warn
+        name: ab-results
+        path: |
+          ab-results-README.md.json
+          ab-results-README.md-filtered.json
+          ab-results-README.md-markdown-table.json
+