Run tests on push/pull request

.github/workflows/run-tests.yml

@@ -0,0 +1,17 @@
+name: Run tests
+
+on:
+  workflow_dispatch:
+  pull_request:
+  push:
+
+jobs:
+  run-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: 8.1
+      - uses: ramsey/composer-install@v3
+      - run: vendor/bin/phpunit