chore: cosmetic cleanup of actions files

[khos2ow]

Some cosmetics cleanup of Github Actions files for better readability. Mostly:

• add empty lines between jobs
• correct indentation of one block

Also renamed one of the actions. This is just a personal preferences and can be removed if you feel like it.

- name: regolith-desktop is installable 2
+ name: Test regolith-desktop is installable