Fix XR Tests for 2019.3

[StayTalm]

In 2019.3 Device Role got replaced with InputDeviceCharacteristics. Updated XRTests to use Characteristics when working in 2019.3 or greater.

[Rene-Damm]

@karljj1 landed a change related to this as part of getting CI back to green. @StayTalm could you merge latest develop and update the PR? Or is it obsoleted by Karl's change?

[StayTalm]

I'll do a merge, I would like to move away from using Role since it's being deprecated, so I'm trying to set Characteristics directly instead of converting from role to characteristics.

[Rene-Damm]

I'll do a merge, I would like to move away from using Role since it's being deprecated, so I'm trying to set Characteristics directly instead of converting from role to characteristics.

Feel free to redo/change the existing fix.

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[jfreire-unity]

To be merged in #1655.