do check/autocompletion on unittest patch string

### Describe the Bug

unittest patch use string to patch obj.

When doing refactor, I rename or reorder the obj, I will need to know where to update the string.

https://docs.python.org/3/library/unittest.mock.html#unittest.mock.patch

example

```
def foo():
...

@patch(...)
def test_...
```

when I rename foo -> bar, I want the patch can show error message.

### Sandbox Link

_No response_

### (Only applicable for extension issues) IDE Information

_No response_