[!!!][TASK] Avoid setMethods() on mocks

setMethods() has been removed with phpunit 10.

$this->getAccessibleMock() used this to only
partially mock a test subject. The patch switches
to onlyMethods() now.

There is one difference: onlyMethods() fails if
a methods that should be mocked does not exist,
while setMethods() did not fail on this.

So this is more strict now. It was frequently used in
core tests mocking ['dummy'] to say "mock no method".
Those have to be switched to use 'null' as argument
to $this->getAccessibleMock() now. Also, when a class
is refactored, and a method that has been previously
mocked is removed with the refactoring, the mock has
to be adapted to remove the method-mock request from
the test as well now, otherwise the test will fail.

Rules for the second argument of getAccessibleMock():

* "keep all methods, mock nothing": Hand over 'null'
* "mock all methods": Hand over empty array [] (default)
* "mock single methods": Hand over an array with method names

Releases: main, 7
Resolves: #444

Build/phpstan/phpstan-baseline.neon

@@ -1,10 +1,5 @@
 parameters:
 	ignoreErrors:
-		-
-			message: "#^Call to an undefined method PHPUnit\\\\Framework\\\\MockObject\\\\MockBuilder\\<T of object&TYPO3\\\\TestingFramework\\\\Core\\\\AccessibleObjectInterface\\>\\:\\:setMethods\\(\\)\\.$#"
-			count: 1
-			path: ../../Classes/Core/BaseTestCase.php
-
 		-
 			message: "#^Instantiated class PHPUnit\\\\Framework\\\\RiskyTestError not found\\.$#"
 			count: 3

Classes/Core/BaseTestCase.php

@@ -124,10 +124,15 @@ protected function getAccessibleMock(
         }
 
         $mockBuilder = $this->getMockBuilder($this->buildAccessibleProxy($originalClassName))
-            ->setMethods($methods)
             ->setConstructorArgs($arguments)
             ->setMockClassName($mockClassName);
 
+        if ($methods === null) {
+            $mockBuilder->onlyMethods([]);
+        } elseif (!empty($methods)) {
+            $mockBuilder->onlyMethods($methods);
+        }
+
         if (!$callOriginalConstructor) {
             $mockBuilder->disableOriginalConstructor();
         }