ignore trailing commas in versions

[matt-phylum]

The documentation says that the current behavior is correct, but the canonical implementation of the documentation accepts trailing commas, and this has been observed in packages.

See pypa/packaging#803 for details.

>>> from packaging.requirements import Requirement
>>>
>>> print(Requirement("numpy >=1.19, "))
numpy>=1.19

[konstin]

Sorry, but i won't accept non-spec extensions for the grammar. If you need to accept invalid versions specifiers (there's a lot of them on pypi historically), consider adding preprocessing (https://github.com/astral-sh/uv/blob/55f6e4e66bb67c6928437f4c6a791c9fc3409d3b/crates/pypi-types/src/lenient_requirement.rs).

[matt-phylum]

The spec has been updated so this should be reopened: https://packaging.python.org/en/latest/specifications/dependency-specifiers/#history