Pip section should allow archive urls and filesystem paths

[costrouc]

Pip allows you to install from archive urls. Currently the following error appears

name: test
dependencies:
 - pip
 - pip:
    - https://github.com/pallets/flask/archive/refs/tags/2.1.2.zip
    - ./path/to/archive.zip # on local machine

Would like for the logic in:

• https://github.com/Quansight/conda-store/blob/main/conda-store-server/conda_store_server/schema.py#L153-L174 updated so that archive urls are also supported. Likely just some check that it is a valid url or local path using the stdlib.
• will need to refine the logic here https://github.com/Quansight/conda-store/blob/main/conda-store-server/conda_store_server/environment.py#L103-L119 on what a pip package is (excluding arguments, archive urls, and filesystem paths).

Generally we would like to handle pip packages similar to how pip normally handles a Requirements.txt file. This may require leveraging the pip library more deeply which I am fine with. Which would certainly be a better fix than what I am suggesting.

Related to https://github.com/Quansight/conda-store/issues/325.