Add error tests in doctest and fix error message (TheAlgorithms#10930)

* Add error tests in doctest and fix error message

* Change AssertationError to ValueError

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 2 people

maths/prime_check.py

@@ -29,12 +29,19 @@ def is_prime(number: int) -> bool:
     True
     >>> is_prime(67483)
     False
+    >>> is_prime(16.1)
+    Traceback (most recent call last):
+        ...
+    ValueError: is_prime() only accepts positive integers
+    >>> is_prime(-4)
+    Traceback (most recent call last):
+        ...
+    ValueError: is_prime() only accepts positive integers
     """
 
     # precondition
-    assert isinstance(number, int) and (
-        number >= 0
-    ), "'number' must been an int and positive"
+    if not isinstance(number, int) or not number >= 0:
+        raise ValueError("is_prime() only accepts positive integers")
 
     if 1 < number < 4:
         # 2 and 3 are primes
@@ -64,7 +71,7 @@ def test_primes(self):
         assert is_prime(29)
 
     def test_not_primes(self):
-        with pytest.raises(AssertionError):
+        with pytest.raises(ValueError):
             is_prime(-19)
         assert not is_prime(
             0