[Feature] Add OS dependencies in ci

[woile]

Hello there! First, thanks for this awesome tool! I did a quick swap of my previous release pipeline with the generated by cargo dist init --ci=github and I got this error:

Package pango was not found in the pkg-config search path.

See pipeline error for more.

It is related to the OS dependencies required by the package. I solved it by adding some steps to the pipeline, and everything worked fine 🎉

I was wondering if I missed something or the approach I took was okay. In the docs, I see a configuring-targets. It would be nice to be able to add required deps per target os. I couldn't find an issue related, I apologize if it's already there.

For example:

[profile.dist.target.os.ubuntu]
deps = "libgtk-3-dev"
[profile.dist.target.os.macos]
deps = "cairo"

Cheers!

[Gankra]

I agree, someone beat you to the punch filing #102 though! :)