Fix test case for zero numerator in isProperFraction

It was a typo error and is fixed now.

Author: Yonatanteklemariam

Sprint-3/1-implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js

@@ -10,7 +10,7 @@ test(`should return false when denominator is zero`, () => {
 });
 
 //Special case: numerator is zero
-test(`should return false when numerator is zero`, () => {
+test(`should return true when numerator is zero`, () => {
   expect(isProperFraction(0, 1)).toEqual(true);
 });
 // Proper functions with absolute numerator < absolute denominator