The content type text/xml; charset=\"utf-8\" of the response message does not match the content type of the binding (text/xml; charset=utf-8)

I am calling a SOAP WCF Service from a new .Net Core WebApi application and am getting the following error:

"The content type text/xml; charset=\"utf-8\" of the response message does not match the content type of the binding (text/xml; charset=utf-8).
If using a custom encoder, be sure that the IsContentTypeSupported method is implemented properly.
The first 1024 bytes of the response were:..."

If I run the application and watch it on Fiddler, I see proper XML data come back. We're good there. Sure enough, the Request Content-Type header is text/xml; charset=utf-8 and the response Content-Type Header is Content-Type: text/xml; charset="utf-8". So yes...there are quotation marks there.

If I peruse the internet, I find the following Stack Overflow question:

https://stackoverflow.com/questions/41684342/the-content-type-text-xml-charset-utf-8-of-the-response-message-does-not-matc

This is exactly my problem and the user of the SO site utilized the following solution:

https://github.com/dotnet/wcf/blob/master/src/System.Private.ServiceModel/tools/IISHostedWcfService/App_code/testhosts/CustomTextMessageEncoder.cs

The thing is, I don't know how to wire that up into my application to get it to work. Can someone provide examples?

Please let me know if there is an easier way or if more information is needed.