[CodeQuality] Skip multiple uses variable as arg after defined on BareCreateMockAssignToDirectUseRector

[samsonasik]

When used multiple times as argument value, it can already changed on caller, so this should be skipped.

        $someMock = $this->createMock(SomeClass::class);

        // behaviour can already changed on first use
        $this->useMock($someMock);
        $this->useMockAgain($someMock);

This PR skip it, this example happen in our project ;)

[samsonasik]

@TomasVotruba ready 👍

[TomasVotruba]

LGTM 👍