Don't follow up or double log on "Unknown interaction" failures

[kevinlul]

This fix applies to Emcee as well.

Sometimes Discord takes too long to send the bot the interaction, so even if the bot immediately replies, it is past the three-second window and thus gets Unknown interaction. The error handler attempts to reply or follow up on any exception when running a command, but this will also fail since the interaction has expired. This ends up double-logging "Unknown interaction". Do not attempt to follow up when the exception type is "Unknown interaction".