title: Returning VS NOT returning a promise in firebase cloud function
body: <p>I'm creating a Firebase cloud function that routes events to another system by making http calls for every event.
  I noticed that if I don't return the promise, the http gets called most of the times (can't be 100% sure). I don't care about the response</p>
  
  <p>Execution time decreases substantially if I don't return it. (155ms vs 13ms) </p>
  
  <p>Does anyone know if a non returned promise is guaranteed to execute? </p>