Doesn't understand the attrs `default` and `converter` arguments correctly

Bug Report

Mypy is complaining about incompatible assignment when it should not, because the default value assigned in the attr.ib() call will be passed to the converter (and be converted). But it seems that mypy do no currently understand that.

attrs docs about order of execution: https://www.attrs.org/en/stable/init.html#order-of-execution

To Reproduce

Code example

from pathlib import Path
import attr
@attr.s
class Options:
    path: Path = attr.ib(default='.', converter=Path)

Expected Behavior

It should not trigger errors.

Actual Behavior

Triggers error: 6: error: Incompatible types in assignment (expression has type "str", variable has type "Path")

Your Environment

• Mypy version used: mypy 0.910
• Mypy command-line flags: Nothing special
• Mypy configuration options from mypy.ini (and other config files): None
• Python version used: 3.8
• Operating system and version: MacOS catalina

Start with the provided Python reproducer and the attrs order-of-execution documentation, then trace mypy's handling of attr.ib() defaults and converters. Done means the example no longer reports an incompatible assignment while existing attrs typing behavior remains correct.