fix typo in binomial_distribution.py output (#14779)

Author: f-p-0

maths/binomial_distribution.py

@@ -36,6 +36,6 @@ def binomial_distribution(successes: int, trials: int, prob: float) -> float:
     from doctest import testmod
 
     testmod()
-    print("Probability of 2 successes out of 4 trails")
+    print("Probability of 2 successes out of 4 trials")
     print("with probability of 0.75 is:", end=" ")
     print(binomial_distribution(2, 4, 0.75))