Pass in permissions boundary to k8s module

[aktech]

The permissions boundary was not passed in properly, as a result you'd see AccessDenied exception, when creating roles without the given permissions boundary.

Reference Issues or PRs

Fixes #2152

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?

Any other comments?

[costrouc]

@aktech would you mind adding to this PR how exactly one would set the permissions_boundary setting

[aktech]

I have added the docs here: nebari-dev/nebari-docs#392
Preview: https://deploy-preview-392--nebari-docs.netlify.app/docs/how-tos/nebari-aws#permissions-boundary-optional