function Deno.addSignalListener
          
addSignalListener(signal: Signal,handler: () => void,): void 
      Registers the given function as a listener of the given signal event.
Deno.addSignalListener(
  "SIGTERM",
  () => {
    console.log("SIGTERM!")
  }
);
Note: On Windows only "SIGINT" (CTRL+C) and "SIGBREAK" (CTRL+Break)
are supported.
signal: Signal
      
    void