PyPI deployment (so micro-sam can be listed on napari-hub)

[GenevieveBuckley]

Closes https://github.com/computational-cell-analytics/micro-sam/issues/530

The napari-hub discovers napari plugins by scraping PyPI, looking for the napari framework classifier. When it finds a package with the napari classifier, it will automatically populate a page on the napari-hub for that plugin.

This PR:

• Adds a deploy job to the release_drafter.yml github workflow. This job runs every time the release drafter workflow runs and the update_release_draft job finishes.
• Updates requirements-dev.txt to include build and twine dependencies (this is not required for the release_drafter.yml action to work, but they are nice to have if you are testing the build locally)
• Adds a section to the installation docs, discouraging users from installing micro-sam with pip. As previously discussed here and here, if users pip install micro-sam then not all of the dependencies will be correctly installed. Some of our dependencies, like affogato are only available from conda-forge. However, we think the benefit of being searchable on napari-hub outweighs this downside.

Still to do: @constantinpape will need to

• [ ] Set up an API token for PyPI, see https://pypi.org/help/#apitoken
• [ ] Add the token as github secrets named PYPI_USERNAME and PYPI_PASSWORD in the settings of this repository, see https://docs.github.com/en/actions/security-guides/using-secrets-in-github-actions#creating-secrets-for-a-repository