Always emitting description for response unless $ref is specified

Author: VitaliyKurokhtin

src/Microsoft.OpenApi/Models/OpenApiResponse.cs

@@ -78,14 +78,7 @@ public void SerializeAsV3WithoutReference(IOpenApiWriter writer)
             writer.WriteStartObject();
 
             // description
-            if (this.Reference == null)
-            {
-                writer.WriteRequiredProperty(OpenApiConstants.Description, Description);
-            }
-            else
-            {
-                writer.WriteProperty(OpenApiConstants.Description, Description);
-            }
+            writer.WriteRequiredProperty(OpenApiConstants.Description, Description);
 
             // headers
             writer.WriteOptionalMap(OpenApiConstants.Headers, Headers, (w, h) => h.SerializeAsV3(w));
@@ -129,14 +122,7 @@ public void SerializeAsV2WithoutReference(IOpenApiWriter writer)
             writer.WriteStartObject();
 
             // description
-            if (this.Reference == null)
-            {
-                writer.WriteRequiredProperty(OpenApiConstants.Description, Description);
-            }
-            else
-            {
-                writer.WriteProperty(OpenApiConstants.Description, Description);
-            }
+            writer.WriteRequiredProperty(OpenApiConstants.Description, Description);
 
             if (Content != null)
             {