Add unit test workflow

Author: tijmenbruggeman

.github/workflows/tests.yml

@@ -0,0 +1,23 @@
+name: Unit Tests
+
+on:
+  push:
+    branches:
+      - '**'
+  pull_request:
+    branches:
+      - '**'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: PHPUnit tests
+        uses: php-actions/phpunit@v3
+        with:
+          configuration: "custom/path/to/phpunit.xml"
+          memory_limit: "256M"