test: create testing functions for average number of guesses over all possible targets

Main.hs

@@ -39,7 +39,4 @@ toChord = fromJust . mapM toPitch . words
 -- | Prompt for a target and use guessTest to try to guess it.
 main :: IO ()
 main = do
-  putStr "Target chord (3 pitches separated by spaces): "
-  hFlush stdout
-  text <- getLine
-  guessTest $ toChord text
+  putStr $ show avgGuesses