use php 8.1 as used by platform.sh

Author: bendavies

.github/workflows/test.yaml

@@ -11,7 +11,7 @@ jobs:
             - uses: actions/checkout@master
             - uses: shivammathur/setup-php@v2
               with:
-                  php-version: '8.0'
+                  php-version: '8.1'
             - uses: ramsey/composer-install@v2
             - name: php-cs-fixer
               run: ./vendor/bin/php-cs-fixer fix --dry-run --diff

ux.symfony.com/composer.json

@@ -4,7 +4,7 @@
     "minimum-stability": "RC",
     "prefer-stable": true,
     "require": {
-        "php": ">=8.0.2",
+        "php": "^8.1",
         "ext-ctype": "*",
         "ext-iconv": "*",
         "babdev/pagerfanta-bundle": "^3.7",