Make `nbdev_new` create settings with `git_url` using `GH_HOST`

[lgonzalezsa]

I am using GH_HOST env variable with my GitHub Enterprise hostname, then expecting the settings.ini reflect that in docs section but still seeing git_url = https://github.com/%(user)s/%(repo)s

I can manually change that but not sure what could be side effect of git_url settings.

### Docs ###
branch = master
custom_sidebar = False
doc_host = https://%(user)s.github.io
doc_baseurl = /%(repo)s
git_url = https://github.com/%(user)s/%(repo)s
title = %(lib_name)s

cc @seeM

[seeM]

It should be fine to change it manually in settings.ini. It affects:

• Links to source in {package}/_modidx.py which are used in the rendered docs [source] link
• Quarto uses it for any of its own links to GH from your website (e.g. "Report an issue" and the GitHub icon on the top-right)
• PyPI and conda packages include it in their metadata (in nbdev_pypi and nbdev_conda respectively)

I've repurposed this issue as a feature request to make nbdev_new use GH_HOST when it creates your initial settings file.

[seeM]

Another thing you can do for now is:

nbdev_new --git_url="$GH_HOST/%(user)s/%(repo)s"

EDIT: This might actually be a better general solution since it also works for other git-hosts like GitLab