Lots of URLs were HTTP redirect to HTTPS. Changed those and checked them if there's actual content. Inspired by https://github.com/NixOS/nixpkgs/issues/60004
Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools. This update was made based on information from https://repology.org/metapackage/python3.7-jupyterlab_server/versions (cherry picked from commit ca67a7200cf9606e132a5eac4a584ef26c48163f)