Add ability to pass user groups to jupyterhub context

[viniciusdc]

Reference Issues or PRs

What does this implement/fix?

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds a feature)
• Breaking change (fix or feature that would cause existing features not to work as expected)
• Documentation Update
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Build related changes
• Other (please describe):

Testing

• Did you test the pull request locally?
• Did you add new tests?

Documentation

Access-centered content checklist

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• The content is written with plain language (where relevant).
• If there are headers, they use the proper header tags (with only one level-one header: H1 or # in markdown).
• All links describe where they link to (for example, check the Nebari website).
• This content adheres to the Nebari style guides.

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• If the content were to be read as plain text, it still makes sense, and no information is missing.

Any other comments?

[viniciusdc]

By including it as part a spawn hook, this should give us the flexibility to use set a fake auth_state in the future, to any features that require this data

[aktech]

@viniciusdc Thanks for this, can you add a couple of lines of docs to mention that shared environments should be accessible to the user?

[viniciusdc]

Sure thing, we are planning to merge this doc with nebari, so all tutorials would be applicable for this. But I will open something under the env section to notify users about this

[viniciusdc]

I included some docs as a first draft

[aktech]

Thanks @viniciusdc this looks good to me. Verified it works.