resolve inconsistency between lint.sh and setup.cfg

[haifeng-jin]

setup.cfg says 80 chars per line, but lint.sh says 200 chars per line. This PR resolves this inconsistency.

The inconsistency between lint.sh and setup.cfg is causing the IDEs to print false lint warnings, because IDEs use setup.cfg only.

Now 80 char line length is only ensured by black.
There are a lot of over length strings, docstrings, and comments.

Ideally, we should still ensure 80 char line length and use # noqa: E501 after the docstrings like the following.

class SomeClass:
    """My docstring.

    This is a line with over length.
    """  # noqa: E501

[LukeWood]

Thanks for the PR! The reason we have this as of now is for links, i.e.

class MyLayer:
    """
    References:
         - https://arxiv.org/my/super/long/link/that/is/10233243232/characters/long/and/definitely/over/80
    """

Open to alternatives, but thats the history of this configuration!

[haifeng-jin]

@LukeWood Thanks for the context!
To be clear, this PR does not change this configuration, but only move the configuration into setup.cfg to make it universal.

We can change it later when we have the resource to do it.

[ianstenbit]

LGTM, thanks Haifeng!

I've opened #1532 for the long-term solution of enforcing 80 universally and exempting docstrings using noqa