Removing a substatus triggers a status email to be sent

[dwhitig]

Describe the bug
If there is a value in the substatus field and you remove that value (set it to none), an email is triggered for the Status value if the Status value has an email configured for it's use. This should not happen as it could cause registration emails to go out again erroneously.

To Reproduce
Steps to reproduce the behavior:

1. Set up an email to get sent when the status = Registered
2. Register a person. They will get the registration email.
3. Edit the registration for the person and add a substatus and save.
4. Go back to the same registration record, edit the substatus and remove it.
5. Another registration email will be sent

Expected behavior
The Status email should only be triggered if the record is new or the Status field is changed. The same for the substatus field otherwise there will be unintended consequences.

Screenshots