py-yarl: updated to 1.9.1

1.9.1 (2023-04-21)
==================

Bugfixes
--------
- Marked tests that fail on older Python patch releases (< 3.7.10, < 3.8.8 and < 3.9.2) as expected to fail due to missing a security fix for CVE-2021-23336.

1.9.0 (2023-04-19)
==================

This release was never published to PyPI, due to issues with the build process.

Features
--------
- Added ``URL.joinpath(*elements)``, to create a new URL appending multiple path elements.
- Made :py:meth:`URL.__truediv__` return ``NotImplemented`` if called with an unsupported type — by :user:`michaeljpeters`.

Bugfixes
--------
- Path normalisation for absolute URLs no longer raises a ValueError exception
  when `..` segments would otherwise go beyond the URL path root.
- Fixed an issue with update_query() not getting rid of the query when argument is None.
- Added some input restrictions on with_port() function to prevent invalid boolean inputs or out of valid port inputs; handled incorrect 0 port representation.
- Made :py:meth:`URL.build` raise a :py:exc:`TypeError` if the ``host`` argument is :py:data:`None` — by :user:`paulpapacz`.
- Fixed an issue with ``update_query()`` getting rid of the query when the argument
  is empty but not ``None``.

(adam)