New review comment by icp1994 on void-packages repository

https://github.com/void-linux/void-packages/pull/42227#discussion_r1104958801

Comment:
The link under the `About` section of https://github.com/py-pdf/pypdf contains the readthedocs site but with hardcoded language version. It's favorable to use rtfd as it will always redirect to the default version of the project whatever it might change to in the future: https://docs.readthedocs.io/en/stable/automatic-redirects.html#rtfd-io