Webhook - Case Management connector `PUT` updates fails to send `Content-Type: application/json` header

Elastic Version: 8.12.0

As the title states, the "Webhook - Case Management" connector PUT update fails to send the Content-Type: application/json HTTP header to case management platform. In my case, the platform is Redmine and it rejects the update due to the missing header.

The initial creation of a ticket within Redmine works fine, but errors when attempting to update the existing ticket. Error text within Kibana:

[Action][Webhook - Case Management]: Unable to update case with id 1. Error: Missing content type header in put https://redmine.local/issues/1.json. Supported content types: application/json.

It should be noted that the Content-Type header was specified during configuration of the connector, but still only seems to be sent during initial creation.

In testing, I reconfigured Redmine to accept the updates without the Content-Type header set - but Kibana still throws the same error.

When creating a new Case in this configuration, if I add Redmine as a connector when there are existing Case comments, then attempt to push the case to Redmine - the corresponding issue will be created correctly in Redmine, but the error is thrown in Kibana upon case push. This causes duplicate Redmine issues to be created each time the push is attempted.

Meanwhile, if a case is created and Redmine is added as a connector before any comments are added - the case is created successfully without error. If comments are added to the case afterward and I click Update Redmine incident - I will get the Kibana error but the Redmine issue is updated successfully.

There error seems to lie in Kibana identifying that it is not sending the Content-Type field, which is an issue within itself.