fix: Fix issues within /mute

[Nydauron]

Description

Fixes a couple of issues within /mute:

• Changes test logic to fetch the new member object rather than referencing the old one.
  • The old one is cached data and doesn't represent the most up-to-date state after timing out the user.
• Add a check to make sure the timestamp provided and used after confirmation is in the future.
  • No timeout would be applied otherwise

Checks

• I ran black over the code to ensure formatting.
• I added docstrings to any new modules, classes, and methods.
• 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]

👍