Add interaction related message flags

[freya022]

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Closes Issue: NaN

Description

This adds the EPHEMERAL and LOADING message flags, the ephemeral flag is particularly useful as you can't determine if a message is ephemeral by checking if GenericComponentInteractionEvent#getMessage is null

Also fixes docs for ComponentInteraction#getMessage and enables editButton and editSelectionMenu methods

[MinnDevelopment]

I think methods such as addReaction, pin, and editMessage should check for this flag and throw an exception. You can't use these methods on ephemeral messages since you get an unknown message error response.

[MinnDevelopment]

You likely need to update the throws docs on these methods to reflect the behavior on ephemeral messages