Make this test work with PHP >= 8.1

tests/end-to-end/mock-objects/generator/3967-php7-php80.phpt

@@ -0,0 +1,61 @@
+--TEST--
+https://github.com/sebastianbergmann/phpunit/issues/3967
+--SKIPIF--
+<?php declare(strict_types=1);
+if (!(new ReflectionMethod(Exception::class, '__clone'))->isFinal()) {
+    print 'skip: PHP < 8.1 required';
+}
+--FILE--
+<?php declare(strict_types=1);
+interface Bar extends \Throwable
+{
+    public function foo(): string;
+}
+
+interface Baz extends Bar
+{
+}
+
+require __DIR__ . '/../../../../vendor/autoload.php';
+
+$generator = new \PHPUnit\Framework\MockObject\Generator;
+
+$mock = $generator->generate(
+    'Baz',
+    [],
+    'MockBaz',
+    true,
+    true
+);
+
+print $mock->getClassCode();
+--EXPECT--
+declare(strict_types=1);
+
+class MockBaz extends Exception implements Baz, PHPUnit\Framework\MockObject\MockObject
+{
+    use \PHPUnit\Framework\MockObject\Api;
+    use \PHPUnit\Framework\MockObject\Method;
+
+    public function foo(): string
+    {
+        $__phpunit_arguments = [];
+        $__phpunit_count     = func_num_args();
+
+        if ($__phpunit_count > 0) {
+            $__phpunit_arguments_tmp = func_get_args();
+
+            for ($__phpunit_i = 0; $__phpunit_i < $__phpunit_count; $__phpunit_i++) {
+                $__phpunit_arguments[] = $__phpunit_arguments_tmp[$__phpunit_i];
+            }
+        }
+
+        $__phpunit_result = $this->__phpunit_getInvocationHandler()->invoke(
+            new \PHPUnit\Framework\MockObject\Invocation(
+                'Bar', 'foo', $__phpunit_arguments, ': string', $this, true
+            )
+        );
+
+        return $__phpunit_result;
+    }
+}

tests/end-to-end/mock-objects/generator/3967.phpt

@@ -1,5 +1,10 @@
 --TEST--
 https://github.com/sebastianbergmann/phpunit/issues/3967
+--SKIPIF--
+<?php declare(strict_types=1);
+if ((new ReflectionMethod(Exception::class, '__clone'))->isFinal()) {
+    print 'skip: PHP >= 8.1 required';
+}
 --FILE--
 <?php declare(strict_types=1);
 interface Bar extends \Throwable
@@ -31,6 +36,7 @@ class MockBaz extends Exception implements Baz, PHPUnit\Framework\MockObject\Moc
 {
     use \PHPUnit\Framework\MockObject\Api;
     use \PHPUnit\Framework\MockObject\Method;
+    use \PHPUnit\Framework\MockObject\UnmockedCloneMethod;
 
     public function foo(): string
     {