feat: Add member role save and restoration on member leave and join

[Nydauron]

Description

Allows for users' roles to be saved upon user leave and then restored upon user rejoin.

Please note that this feature is intended to only restore non-publicly assignable roles (i.e. roles that cannot be assigned via the onboarding survey). Some examples of roles that are non-publicly assignable include but are not limited to Exalted, Automation Development Subgroup, Muted, and Quarantine.

Currently, these roles are hard-coded into a list. Ideally, this list should be able to be changed during runtime, so consideration of making it its own database table is not out of the question.

Checks

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• I updated the docstrings of any updated modules, classes, and methods.
• I added/updated Python typings for any new/updated class and module.
• I updated the bot version (if necessary).
• I ran mypy and reviewed any shown errors related to my changes.

Important Info

• This pull request adds new pip dependencies.
• This pull request adds new external dependencies.
• This pull request changes the required versions of some dependencies.

Issues Closed

My pull request closes the following issues:
N/A

Thank You

Thank you for your contribution to Scioly.org! This pull request will be reviewed
in a promptly manner. If not done, please feel free to contact @cbrxyz.

[Nydauron]

👍