Move tests to github

.github/workflows/test.yml

@@ -0,0 +1,19 @@
+name: Test
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install dependencies
+        run: docker run --rm -v $PWD:/code --entrypoint='' humanmade/plugin-tester composer install
+
+      - name: Run tests
+        run: docker run --rm -v $PWD:/code humanmade/plugin-tester

composer.json

@@ -11,6 +11,7 @@
     ],
     "require": {},
     "require-dev": {
-        "phpunit/phpunit": "^7"
+        "phpunit/phpunit": "^7",
+        "yoast/phpunit-polyfills": "^4.0"
     }
 }