pkg_resources deprecation warning from myproxy

[alaniwi]

After installing the latest esgpull into a conda environment containing Python 3.13, I am seeing this.

$ esgpull --version
[...]/lib/python3.13/site-packages/myproxy/__init__.py:1: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.
  __import__('pkg_resources').declare_namespace(__name__)
esgpull, version 0.9.2

(Installation path redacted as [...] above.)

Is this a good opportunity to remove the support for client certificates, which should not be needed any more? Then there is no more need for myproxy.client.

[svenrdz]

For sure, I'll remove this dependency in the next release ! The login command should also go away, since it is only used for managing the certificates.