Anki gives ModuleNotFoundError without pip_system_certs installed

[escape0707]

As of version 24.04, if pip_system_certs module is not installed on the system, running Anki will error like this:

$ anki
Traceback (most recent call last):
  File "/usr/bin/anki", line 17, in <module>
    import aqt
  File "/usr/lib/python3.11/site-packages/aqt/__init__.py", line 9, in <module>
    import pip_system_certs.wrapt_requests
ModuleNotFoundError: No module named 'pip_system_certs'

This dependency is introduced by #3050, to solve #3016, and the original bug report is on MacOS with a niche network setup. This dependency does not benefit normal Linux users using Anki with their system packages at all, as most Linux distros have already configured their python-requests module to use system certificate instead, also most users don't have this niche network setup.

This pip_system_certs module is not packaged officially for most Linux distros e.g. Fedora, Ubuntu, Debian, Arch. It has only 12 stars on GitLab. And will break existing binary installation process. It will be better if we can catch and ignore the ModuleNotFoundError thus make this dependency an optional one.