Automate homework checking

.github/workflows/main.yml

@@ -0,0 +1,22 @@
+name: CheckHomework
+
+on: [pull_request]
+
+jobs:
+  check:
+    if: contains(github.repository,'HackYourHomework')
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: '10.x'
+      - run: npm install
+      - name: Echo week folder and run tests
+        run: |
+          echo ${{github.repository}}
+          echo ${{github.head_ref}}
+          declare WEEK
+          WEEK=$(echo "${{github.head_ref}}" | sed -E 's/.*w(eek)?[-_]?([0-9]).*/week\2/gi')
+          echo Week: "${WEEK}"
+          npm run test-"${WEEK}"