ESP32 Webinterface to control a relay board for antenna switching
It is a slightly changed version of the one published by Rui Santos from randomnerdtutorials: https://RandomNerdTutorials.com/esp32-relay-module-ac-web-server/
It only allows one relay active at a time which is needed for antenna switching in a ham-radio application. This change was only done for the NO (normally open) part of the sketch.