incorrect types for functions decorated with `@mock.patch`

[svalentin]

Looks like we have a typeshed bug:

from unittest.mock import patch

def addition(a: int, b:int) -> int:
    return a+b

@patch('test.addition')
def patch_test(mock):
    print(mock)

if __name__ == "__main__":
    patch_test()

In this simple example mypy says:

test.py:12: error: Missing positional argument "mock" in call to "patch_test"  [call-arg]

Undoing 9e86c60 fixes it