Provide error if the Jira webhook "Exclude body" checkbox is selected

When configuring a webook in Jira, there is a checkbox:

• ☐

  "Exclude body" Request with empty body will be sent to the URL. Leave unchecked if you want to receive JSON.

If someone accidentally checks that, Aha! won't get any updates.

There is no log message indicating that the webhook is working at all.

It would be helpful to show a message in the logs or in the integration settings advising the user to uncheck the "Exclude body" setting.