Add `DeferrableInteractionCallbackAction`

[freya022]

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Closes Issue: NaN

Description

This PR adds DeferrableInteractionCallbackAction, which is extended by ReplyCallbackAction and MessageEditCallbackAction, allowing to retrieve the InteractionHook when replying/editing a message with an interaction.

My use case is to create extensions such as:

fun <R> DeferrableInteractionCallbackAction<R>.deleteAfter(duration: Duration): RestAction<R> =
    delay(duration).onSuccess { hook.deleteOriginal() }

[MinnDevelopment]

Is this not enough?

fun RestAction<InteractionHook>.deleteAfter(duration: Duration): RestAction<InteractionHook>
    = delay(duration.toJavaDuration())
        .flatMap { hook -> hook.deleteOriginal().map { hook } }

[freya022]

Is this not enough?

fun RestAction<InteractionHook>.deleteAfter(duration: Duration): RestAction<InteractionHook>
    = delay(duration.toJavaDuration())
        .flatMap { hook -> hook.deleteOriginal().map { hook } }

I think it is enough, but wouldn't using onSuccess be simpler?