Do not use deprecated ::set-output any more

cf. https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

Signed-off-by: Sven Strickroth <email@cs-ware.de>

.github/workflows/php.yml

@@ -18,7 +18,7 @@ jobs:
     - name: Get composer cache directory
       if: ${{ !env.ACT }}
       id: composer-cache
-      run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+      run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
 
     - name: Cache dependencies
       if: ${{ !env.ACT }}
@@ -74,7 +74,7 @@ jobs:
     - name: Get composer cache directory
       if: ${{ !env.ACT }}
       id: composer-cache
-      run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+      run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
 
     - name: Cache dependencies
       if: ${{ !env.ACT }}