Merge branch '5.1' into 5.x

* 5.1:
  Disable platform checks
  Put branch-version in the source for CI
  Bump default PHPUnit version for PHP 8 to 9.4.

Author: nicolas-grekas

bin/simple-phpunit.php

@@ -95,7 +95,7 @@
 
 if (\PHP_VERSION_ID >= 80000) {
     // PHP 8 requires PHPUnit 9.3+
-    $PHPUNIT_VERSION = $getEnvVar('SYMFONY_PHPUNIT_VERSION', '9.3');
+    $PHPUNIT_VERSION = $getEnvVar('SYMFONY_PHPUNIT_VERSION', '9.4');
 } elseif (\PHP_VERSION_ID >= 70200) {
     // PHPUnit 8 requires PHP 7.2+
     $PHPUNIT_VERSION = $getEnvVar('SYMFONY_PHPUNIT_VERSION', '8.3');