Use Ubuntu as base system instead of Alpine

[ChristophShyper]

Allows using ppa:git-core/ppa to get git version newer thn the bugged one.

:memo: Brief description

:computer: Commits

:file_folder: Modified files

:warning: Additional information

• [ ] Pushed to a branch with a proper name and provided proper commit message.
• [ ] Provided a clear and concise description of what the issue is.

Check CONTRIBUTING.md and CODE_OF_CONDUCT.md for more information