Pull out versions into its own script

[allenwang28]

Primarily meant to keep the source of truth of commits / packaging in its own file. Additionally changes update_wheels and install to use it.

Other build_wheels changes:

• Instead of doing resume_from etc., you just provide the name of the packages you want installed
• if it can't find the environment variables for whatever reason, it fails.

Not changing CI to do this yet because that is still a WIP cc @ebsmothers