Add test to bump up test coverage

Author: MaggieKimani1

test/Microsoft.OpenApi.Tests/Models/OpenApiMediaTypeTests.cs

@@ -6,6 +6,7 @@
 using FluentAssertions;
 using Microsoft.OpenApi.Any;
 using Microsoft.OpenApi.Extensions;
+using Microsoft.OpenApi.Interfaces;
 using Microsoft.OpenApi.Models;
 using Xunit;
 using Xunit.Abstractions;
@@ -426,5 +427,21 @@ public void SerializeMediaTypeWithObjectExamplesAsV3JsonWorks()
             expected = expected.MakeLineBreaksEnvironmentNeutral();
             actual.Should().Be(expected);
         }
+
+        [Fact]
+        public void MediaTypeCopyConstructorWorks()
+        {
+            var clone = new OpenApiMediaType(MediaTypeWithObjectExamples)
+            {
+                Example = 42,
+                Examples = new Dictionary<string, OpenApiExample>(),
+                Encoding = new Dictionary<string, OpenApiEncoding>(),
+                Extensions = new Dictionary<string, IOpenApiExtension>()
+            };
+
+            // Assert
+            MediaTypeWithObjectExamples.Examples.Should().NotBeEquivalentTo(clone.Examples);
+            MediaTypeWithObjectExamples.Example.Should().Be(null);
+        }
     }
 }