Separate sheet2linkml into its own repository

[gaurav]

This program does something quite different from rest of this repository, so we should probably move it elsewhere. We can then publish it to PyPI and import it for use by this repository, and maintain separate tests in the other repository (#12).

Also:

• When creating its setup.py file, note that it requires a minimum of Python 3.9 since it uses generic types.

(see #8 and #95 for previous discussions of this issue)

[sujaypatil96]

Linking this to the sheet2linkml package on Github and sheet2linkml project on PyPI.

I think this issue is ready to be closed.

[gaurav]

Let's close it after we remove sheet2linkml from this repo? I think we still need to figure out how and where to call sheet2linkml in order to generate a new CRDC-H in LinkML model (#16) -- I'm not sure if those GitHub Actions should be here or in the sheet2linkml repo?

[sujaypatil96]

I think we should be good to close this issue once PR #128 has been merged.