Drop PHPUnit 11 for now

It turns out it does not work due to changes in PHPUnit (missing traits like TestListenerDefaultImplementation).

Tests were not failing before as other dependencies were preventing the PHPUnit from updating to 11.

Re #47

Author: jakzal

composer.json

@@ -4,7 +4,7 @@
     "type": "library",
     "require": {
         "php": "~8.1.0 || ~8.2.0 || ~8.3.0",
-        "phpunit/phpunit": "^9.0 || ^10.0 || ^11.0",
+        "phpunit/phpunit": "^9.0 || ^10.0",
         "psr/container": "^1.0 || ^2.0",
         "zalas/injector": "^2.0"
     },

tests/phar/phpunit.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/8.0/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="../../vendor/phpunit/phpunit/phpunit.xsd"
          beStrictAboutOutputDuringTests="true"
          beStrictAboutTodoAnnotatedTests="true"
          verbose="true"