Path-based source pypi distributions

[pablovela5620]

Checks

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pixi, using pixi --version.

Reproducible example

https://github.com/kcheng1021/GaussianPro
wanted to try out the most recent pixi import from a conda environment from a the recently released GaussianPro model and get the following error from this environment.yml

pixi init --import environment.yml 

environment.yml file

name: gaussianpro
channels:
  - pytorch
  - conda-forge
  - defaults
dependencies:
  - cudatoolkit=11.6
  - plyfile=0.8.1
  - python=3.7.13
  - pip=22.3.1
  - pytorch=1.12.1
  - torchaudio=0.12.1
  - torchvision=0.13.1
  - tqdm
  - pip:
    - submodules/diff-gaussian-rasterization
    - submodules/simple-knn

error

pixi init --import environment.yml
  × Expected one of `@`, `(`, `<`, `=`, `>`, `~`, `!`, `;`, found `/`
  │ submodules/diff-gaussian-rasterization
  │           ^

Issue description

Looks to be an issue with Path-based source pypi distributions

Expected behavior

Should install each pypi package

[ruben-arts]

We currently don't support path based distributions. This will be coming soon!

[ruben-arts]

Closing this in favor of #879