ServicePulse does not show body of the error messages

[HEskandari]

ServicePulse 1.32.1 has issues displaying message bodies of type XML (or anything other than JSON to be specific). Here are the steps to reproduce the issue:

1. Have an endpoint with a default serializer (XML) emit messages that go into the error queue
2. Save service control ingest those messages
3. Open ServicePulse to display error messages and change the tab to the message body
4. Note the message body is not displayed
5. Check the network tab (in DevTools) and see that the query is made to ServiceControl and the response is coming back in form of a XML document

It is expected for XML or textual-based serializer to show the raw message, or show a graceful error message / placeholder, if the content can't be shown (e.g. a binary serializer, or encrypted messages).