ci: add symfony 6.3 to the matrix

Author: williarin

.github/workflows/test.yml

@@ -42,7 +42,7 @@ jobs:
 
             -   name: Get composer cache directory
                 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
                 uses: actions/cache@v3
@@ -65,7 +65,7 @@ jobs:
         strategy:
             matrix:
                 php: ['8.1']
-                symfony: ['6.1', '6.2']
+                symfony: ['6.1', '6.2', '6.3']
 
         steps:
             -   uses: FranzDiebold/github-env-vars-action@v2