op if there is a power adaptor plugged in to the socket, chances are the other end is DC. Under 12V and under 1A. You can touch that end without being hit with electricity. You can just unplug the power adaptor from the wall, lift the other end from the toilet, wash it a lot and let it dry.
If you do not feel safe doing that, turn off the breaker from the distribution panel. If you don't know which breaker the wash-room is hooked up to, turn off the main breaker, that would render your house powerless, but you won't be able to shock yourself.