fix(config): deprecate the report_as field for challenges

This was a bad idea when it was added and it is irresponsible to
continue to have it. It causes more UX problems than it fixes with
slight of hand.

Closes: #1310
Closes: #1307
Signed-off-by: Xe Iaso <me@xeiaso.net>

lib/anubis_test.go

@@ -464,10 +464,6 @@ func TestCheckDefaultDifficultyMatchesPolicy(t *testing.T) {
 			if bot.Challenge.Difficulty != i {
 				t.Errorf("Challenge.Difficulty is wrong, wanted %d, got: %d", i, bot.Challenge.Difficulty)
 			}
-
-			if bot.Challenge.ReportAs != i {
-				t.Errorf("Challenge.ReportAs is wrong, wanted %d, got: %d", i, bot.Challenge.ReportAs)
-			}
 		})
 	}
 }