Only disconnect the relevant server in VoiceBot#destroy
Only disconnect the relevant server in VoiceBot#destroy

megumisonoda/discordrb,Roughsketch/discordrb,VxJasonxV/discordrb,VxJasonxV/discordrb,Roughsketch/discordrb,meew0/discordrb,megumisonoda/discordrb,meew0/discordrb