Drop unsupported versions of PHP

This should allow us to do many breaking changes related to new features
of PHP.

I'm bumping to 8.1 and not higher for the sake of consistency with other
recent versions of Doctrine packages.

.github/workflows/continuous-integration.yml

@@ -14,7 +14,7 @@ jobs:
     name: "PHPUnit"
     uses: "doctrine/.github/.github/workflows/[email protected]"
     with:
-      php-versions: '["7.2", "7.3", "7.4", "8.0", "8.1", "8.2", "8.3", "8.4"]'
+      php-versions: '["8.1", "8.2", "8.3", "8.4"]'
     secrets:
       CODECOV_TOKEN: "${{ secrets.CODECOV_TOKEN }}"
 

composer.json

@@ -20,7 +20,7 @@
         }
     ],
     "require": {
-        "php": "^7.2|^8.0",
+        "php": "^8.1",
         "symfony/deprecation-contracts": "^2.1 || ^3",
         "symfony/framework-bundle": "^5.4 || ^6.0 || ^7.0",
         "doctrine/doctrine-bundle": "^2.4",