Remove null tests

Author: Kalkwst

Algorithms.Tests/Strings/Similarity/OptimalStringAlignmentTests.cs

@@ -70,25 +70,5 @@ public void Calculate_MultipleOperations_ReturnsCorrectDistance()
             var result = OptimalStringAlignment.Calculate("kitten", "sitting");
             result.Should().Be(3.0);
         }
-
-        [Test]
-        public void Calculate_FirstStringNull_ThrowsArgumentNullException()
-        {
-            string? nullString = null;
-#nullable disable
-            Action act = () => OptimalStringAlignment.Calculate(nullString, "example");
-#nullable restore
-            act.Should().Throw<ArgumentNullException>().WithMessage("*firstString*");
-        }
-
-        [Test]
-        public void Calculate_SecondStringNull_ThrowsArgumentNullException()
-        {
-            string? nullString = null;
-#nullable disable
-            Action act = () => OptimalStringAlignment.Calculate("example", nullString);
-#nullable restore
-            act.Should().Throw<ArgumentNullException>().WithMessage("*secondString*");
-        }
     }
 }