Add test case for opting into using the data mismatch validation rule

Author: MaggieKimani1

test/Microsoft.OpenApi.Tests/Validations/OpenApiHeaderValidationTests.cs

@@ -31,7 +31,10 @@ public void ValidateExampleShouldNotHaveDataTypeMismatchForSimpleSchema()
             };
 
             // Act
-            var validator = new OpenApiValidator(ValidationRuleSet.GetDefaultRuleSet());
+            var defaultRuleSet = ValidationRuleSet.GetDefaultRuleSet();
+            defaultRuleSet.Add(typeof(OpenApiHeader), OpenApiNonDefaultRules.HeaderMismatchedDataType);
+            var validator = new OpenApiValidator(defaultRuleSet);
+
             var walker = new OpenApiWalker(validator);
             walker.Walk(header);
 
@@ -40,7 +43,7 @@ public void ValidateExampleShouldNotHaveDataTypeMismatchForSimpleSchema()
             var result = !warnings.Any();
 
             // Assert
-            result.Should().BeTrue();
+            result.Should().BeFalse();
         }
 
         [Fact]

test/Microsoft.OpenApi.Tests/Validations/OpenApiParameterValidationTests.cs

@@ -141,7 +141,10 @@ public void ValidateExamplesShouldNotHaveDataTypeMismatchForSimpleSchema()
             };
 
             // Act
-            var validator = new OpenApiValidator(ValidationRuleSet.GetDefaultRuleSet());
+            var defaultRuleSet = ValidationRuleSet.GetDefaultRuleSet();
+            defaultRuleSet.Add(typeof(OpenApiParameter), OpenApiNonDefaultRules.ParameterMismatchedDataType);
+
+            var validator = new OpenApiValidator(defaultRuleSet);
             validator.Enter("{parameter1}");
             var walker = new OpenApiWalker(validator);
             walker.Walk(parameter);
@@ -150,7 +153,7 @@ public void ValidateExamplesShouldNotHaveDataTypeMismatchForSimpleSchema()
             var result = !warnings.Any();
 
             // Assert
-            result.Should().BeTrue();
+            result.Should().BeFalse();
         }
 
         [Fact]

test/Microsoft.OpenApi.Tests/Validations/OpenApiSchemaValidationTests.cs

@@ -174,15 +174,17 @@ public void ValidateDefaultShouldNotHaveDataTypeMismatchForComplexSchema()
             };
 
             // Act
-            var validator = new OpenApiValidator(ValidationRuleSet.GetDefaultRuleSet());
+            var defaultRuleSet = ValidationRuleSet.GetDefaultRuleSet();
+            defaultRuleSet.Add(typeof(OpenApiSchema), OpenApiNonDefaultRules.SchemaMismatchedDataType);
+            var validator = new OpenApiValidator(defaultRuleSet);
             var walker = new OpenApiWalker(validator);
             walker.Walk(schema);
 
             warnings = validator.Warnings;
             bool result = !warnings.Any();
 
             // Assert
-            result.Should().BeTrue();
+            result.Should().BeFalse();
         }
 
         [Fact]