revert demo domain url (PhotonVision#2218)

Author: TheTripleV

README.md

@@ -17,7 +17,7 @@ If you are interested in contributing code or documentation to the project, plea
 ## Documentation
 
 - Our main documentation page: [docs.photonvision.org](https://docs.photonvision.org)
-- Photon UI demo: [http://photonvision.global/](http://photonvision.global/)
+- Photon UI demo: [demo.photonvision.org](https://demo.photonvision.org)
 - Javadocs: [javadocs.photonvision.org](https://javadocs.photonvision.org)
 - C++ Doxygen  [cppdocs.photonvision.org](https://cppdocs.photonvision.org)
 

docs/source/docs/quick-start/camera-calibration.md

@@ -8,7 +8,7 @@ If you’re not using cameras in 3D mode, calibration is optional, but it can st
 
 ## Print the Calibration Target
 
-- Downloaded from our [demo site](http://photonvision.global/#/cameras), or directly from your coprocessors cameras tab.
+- Downloaded from our [demo site](https://demo.photonvision.org/#/cameras), or directly from your coprocessors cameras tab.
 - Use the ChArUco calibration board:
   - Board Type: ChAruCo
   - Tag Family: 4x4