fix: removed stacktrace printing when result error is set (#119)

We don't need stack trace to be printed when we return the exception in the result.error as it will be returned in the reject callback.
Fixes https://github.com/NativeScript/tns-core-modules-widgets/issues/118

android/widgets/src/main/java/org/nativescript/widgets/Async.java

@@ -561,7 +561,6 @@ public class Async
 				}
 				catch (Exception e) // TODO: Catch all exceptions?
 				{
-					e.printStackTrace();
 					result.error = e;
 
 					return result;
@@ -595,4 +594,4 @@ public class Async
 			}
 		}
 	}
-}
+}