ostree: fix proxy parsing (HMS-5018)

[lzap]

Finally found the ostree resolving problem - it was in proxy parsing. The configuration value is not in URL form, it is in hostname:port form. And url.Parse silently parses such URI setting a nonsense scheme to hostname. TIL that URL in Go actually is technically URI: https://pkg.go.dev/net/url

[lzap]

I did split the OTK hunks into a separate PR: #1051

[croissanne]

wow, nice find :)

[ezr-ondrej]

Nice find! Thanks! 🎉

[mvo5]

Would it make sense to add a regression test here? Also in the "test-as-documentation" sense this might be useful(?)

[ezr-ondrej]

It would make sense to add test for sure... I'd prefer a follow-up tho, I wouldn't like to block this, unless someone disagrees.

[lzap]

Would it make sense to add a regression test here?

I can do a followup, I actually tried by running a tiny HTTP proxy via library but it was not great test to be honest.

[mvo5]

Would it make sense to add a regression test here?

I can do a followup, I actually tried by running a tiny HTTP proxy via library but it was not great test to be honest.

Cool, we don't need to block on this, I had a quick look and opened #1052 - it's not ideal as it's not a full integration test but OTOH I think the extraction of the helper is beneficial and it does check that the proxy is correctly set (but it does know a bit too much about the implementation details for my taste).