issue #4224 Fixing the constraint app-4 for Appointment.status = noshow

[mudlej]

This PR closes issue #4224.

[lmsurpre]

Thanks for your patience, @mudlej

Is it possible for you to amend your commits to include a "sign-off" line in accordance with https://github.com/LinuxForHealth/FHIR/blob/main/CONTRIBUTING.md#legal ?

Alternatively, if you indicate here your agreement to https://developercertificate.org/ then I will override the DCO status.

[mudlej]

I couldn't change the first commit message. But I did for the others, and I say it here as well. I agree to the DCO in https://developercertificate.org/