fix: Better User experience BioID Script

## Recommended improvement for better user experience.

1. We noticed that you have been using mainly our defaults.
2. In terms of traits, you have been using both face and periocular (our defaults).
3. In addition, you have been capturing a total of 4 images for both Enroll/Verify.
4. The above may cause some unnecessary retries.

Recommendation:
Change to face-only.
Capture only 2 images.

How:
Add a parameter when requesting for a Token by using the parameter 'traits=Face'.
Capture only two images, i.e. 'recordings = 2':
(1) look straight at the camera - capture 1st image, and
(2) prompt the user to nod - capture 2nd image using our motion trigger.