feat(flags): implement new member flags

[Snipy7374]

Summary

• Closes implement new member flags #1245

Checklist

• If code changes were made, then they have been tested
  • I have updated the documentation to reflect the changes
  • I have formatted the code properly by running pdm lint
  • I have type-checked the code by running pdm pyright
• This PR fixes an issue
• This PR adds something new (e.g. new method or parameters)
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, ...)

[shiftinv]

some tiny adjustments - the new attributes should also all have a .. versionadded::.
Other than that, lgtm!

[shiftinv]

Suggested change

	Implement :attr:`.MemberFlags.is_guest`, :attr:`.MemberFlags.started_home_actions`, :attr:`.MemberFlags.completed_home_actions`, :attr:`.MemberFlags.automod_quarantined_username`, :attr:`.MemberFlags.dm_settings_upsell_acknowledged` new member flags.
	Implement :attr:`~MemberFlags.is_guest`, :attr:`~MemberFlags.started_home_actions`, :attr:`~MemberFlags.completed_home_actions`, :attr:`~MemberFlags.automod_quarantined_username`, :attr:`~MemberFlags.dm_settings_upsell_acknowledged` new member flags.