Package update

[hoxbro]

The following updates:

• Don't use pyctdev for the PyPI package. Instead, use the build package.
• Splitting building and publishing up for both PyPI and Conda.
• Add artifacts to both
• Add pip install step to check if the wheel can be installed, and do an import.
• Add an approval step after the build and wait for all builds.
• As both build steps take under two minutes to finish, I have set it up so they run on PRs. I am not sure about if this is needed. I can remove it again.

Example of workflow: https://github.com/holoviz/holoviews/actions/runs/7210047765

Screenshots of workflow:

Ref:

• https://timheuer.com/blog/add-approval-workflow-to-github-actions/
• https://packaging.python.org/en/latest/guides/publishing-package-distribution-releases-using-github-actions-ci-cd-workflows/
• https://github.blog/changelog/2023-12-14-github-actions-artifacts-v4-is-now-generally-available/