no AR support for webxr

[0xhrsh]

Describe the bug
setting arModes to ['webxr'] does not show a button for AR.

To reproduce
Steps to reproduce the behavior:

1. Set arModes to ['webxr']
2. Run the app
3. See error

Expected behavior
setting arModes to webxr should display the View in AR button.

Smartphone (please complete the following information):

• Device: [e.g. Samsung galaxy m31]
• OS: [e.g. android 11]