Bump black from 20.8b1 to 21.5b1 (#591)

* Bump black from 20.8b1 to 21.5b1

Bumps [black](https://github.com/psf/black) from 20.8b1 to 21.5b1.
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](https://github.com/psf/black/commits)

Signed-off-by: dependabot[bot] <support@github.com>

* Fix formatting

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Andrew Svetlov <andrew.svetlov@gmail.com>

requirements/lint.txt

@@ -1,5 +1,5 @@
 mypy==0.812; implementation_name=="cpython"
 flake8==3.9.2
 flake8-pyi==20.10.0; python_version >= "3.6"
-black==20.8b1; python_version >= "3.6" and implementation_name=="cpython"
+black==21.5b1; python_version >= "3.6" and implementation_name=="cpython"
 mypy-extensions==0.4.3; implementation_name=="cpython"

yarl/__init__.pyi

@@ -13,6 +13,7 @@ _QueryVariable = Union[_SimpleQuery, Sequence[_SimpleQuery]]
 _Query = Union[
     None, str, Mapping[str, _QueryVariable], Sequence[Tuple[str, _QueryVariable]]
 ]
+
 @final
 class URL:
     scheme: Final[str]