Update README.md

Co-authored-by: Martin Costello <martin@martincostello.com>

README.md

@@ -322,7 +322,7 @@ _NOTE: In previous versions of the docs, you may have seen this expressed as a r
 ### Customizing how the OpenAPI document is serialized ###
 
 By default, Swagger will serialize the OpenAPI document using the Serialize methods on the OpenAPI document object. If a customized serialization is desired, 
-it is possible to create a custom document serializer that implements the `ISwaggerDocumentSerializer` interface. This can be set on the SwaggerOptions in the service collection using ConfigureSwagger():
+it is possible to create a custom document serializer that implements the `ISwaggerDocumentSerializer` interface. This can be set on the `SwaggerOptions` in the service collection using `ConfigureSwagger()`:
 
 _NOTE: If you plan on using the commandline tool to generate OpenAPI specification files, this must be done on the service collection using ConfigureSwagger()._