Update PHPUnit setup

composer.json

@@ -13,7 +13,7 @@
     "ext-reflection": "*"
   },
   "require-dev": {
-    "phpunit/phpunit": "^7.5 || ^8.5 || ^9.0",
+    "phpunit/phpunit": "^9.0 || ^10.0 || ^11.0",
     "phpstan/phpstan": "~1.10.3",
     "phpstan/extension-installer": "^1.0",
     "phpstan/phpstan-strict-rules": "^1.0"

phpunit.xml

@@ -1,17 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/6.0/phpunit.xsd"
-         colors="true"
-         bootstrap="vendor/autoload.php"
->
-    <testsuites>
-        <testsuite name="CallbackValidator Test Suite">
-            <directory>./tests</directory>
-        </testsuite>
-    </testsuites>
-    <filter>
-        <whitelist>
-            <directory>./src</directory>
-        </whitelist>
-    </filter>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.0/phpunit.xsd" colors="true" bootstrap="vendor/autoload.php" cacheDirectory=".phpunit.cache">
+  <testsuites>
+    <testsuite name="CallbackValidator Test Suite">
+      <directory>./tests</directory>
+    </testsuite>
+  </testsuites>
+  <source>
+    <include>
+      <directory>./src</directory>
+    </include>
+  </source>
 </phpunit>