Update list of CHT dev instances and reference apps

[mrsarm]

The list of reference apps and CHT instances is outdated.

Tasks

• [ ] Disable Simprints for now (integration is not working, and dev environment down):
  • [x] Disable the app in the Play Store
  • [ ] Disable the flavor from the list of apps built when releasing
  • [ ] Remove from the list of reference apps in the README
• [ ] Add https://demo-cht.dev.medicmobile.org/ :
  • [ ] Add it to the list of CHT instances in the Unbranded flavor
  • [ ] Re-enable the Demo App (medicmobiledemo flavor) but pointing to this instance instead:
    • [ ] In the code re-enable it in the releases in CI, and change the URL
    • [ ] Add it again in the list of reference apps in the README
    • [ ] Re-enable it in the Play Store: in order to publish the latest version we have to release v0.10.0-1