Update GH Action to install specific PHP versions

Just copy the laravel/laravel setup config. Life's too short.

.github/workflows/lint-and-test.yml

@@ -9,10 +9,25 @@ on:
 jobs:
   lint-and-test:
     runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: true
+      matrix:
+        php: [8.2, 8.3]
+
+    name: PHP ${{ matrix.php }}
+
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
 
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: dom, curl, libxml, mbstring, zip, pcntl, pdo, sqlite, pdo_sqlite
+          coverage: none
+
       - name: Validate composer.json and composer.lock
         run: composer validate --strict