Support URL source dependencies

[pavelzw]

pixi-pack/src/pack.rs

Lines 271 to 273 in 62cb4f6

	UrlOrPath::Url(u) => {
	anyhow::bail!("Unexpected URL for local package source: {}", u)
	}

the following workspace cannot be pixi-packed right now:

[workspace]
preview = ["pixi-build"]
channels = ["conda-forge"]
platforms = ["linux-64", "linux-aarch64", "win-64", "osx-64", "osx-arm64"]

[dependencies]
agent-skill-conda-forge = { git = "https://github.com/pavelzw/skill-forge", rev = "main", subdirectory = "recipes/conda-forge" }