allow using either `--file` or `--sync-dir` + allow use of relative path in args

[Araxeus]

• allow using either --file or --sync-dir without needing the other

• allow use of relative path in args

those changes combined can for example enable the following command in a monorepo:ㅤ

peru reup --file="./packages/$target_package/peru.yml"

fix #235

Note

• This is my first time writing any code in Python, so please excuse me if I made some mistake
• I'm not sure why both of those options were not allowed in the first place? weird… maybe I'm missing something?

[Araxeus]

Good thing that tests exist

Forgot to add the following line so cache dir wasnt properly set env.get('PERU_CACHE_DIR')

And one test is failing because it checked that settings --file and --sync-dir together should throw

I'll push a fix later today

[Araxeus]

@oconnor663 I Pushed fixes for the failing tests, could you approve the running the tests again, please? And also on the other PR? 😅

(tho the current matrix testing is broken since it requires some older python versions that don't exist on the GitHub runner)

[Araxeus]

@oconnor663 heyo :)

[oconnor663]

Thanks for the ping. Apologies for leaving this hanging so long. I've been spending less time on open source stuff in general this year.

[Araxeus]

All test are passing except those that depand on non-existant local python versions 🎉