ci: Update GitHub actions

Author: mbaumgartl

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
         php-versions: ['8.2', '8.3', '8.4', '8.5']
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
@@ -23,7 +23,7 @@ jobs:
         run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
 
       - name: Cache dependencies
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: ${{ steps.composer-cache.outputs.dir }}
           key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}