Use discord's ephemeral messages instead of direct messages

[lMartin3]

Is your feature request related to a problem? Please describe.
Currently, users need to enable private messges in order to recieve their code.

Describe the solution you'd like
The bot could make use of discord's ephemeral messages.

Describe alternatives you've considered
Revert the link flow, the user would recieve the code via Minecraft instead of Discord. This would be harder to implement.