[PHPUnit 12] Add CreateStubOverCreateMockArgRector

[TomasVotruba]

Since PHPUnit 12, you get notice for using mocks without any expectations.

Instead, the createStub() should be used instead:

final class SomeTest extends TestCase
{
    public function test()
    {
        // HERE ↓
-       $this->someMethod($this->createMock(SomeClass::class));
+       $this->someMethod($this->createStub(SomeClass::class));
    }

    private function someMethod($someClass)
    {
    }
}

[samsonasik]

first class callable check needs to be checked early here

[samsonasik]

I created PR:

• [PHPUnit 12] Skip first class callable on CreateStubOverCreateMockArgRector #612

to fix it.