The "select" voice command no longer fires an event on Windows Mixed Reality

[keveleigh]

Does this affect the legacy HoloToolkit (master) or the Mixed Reality Toolkit (mrtk_release)?
Mixed Reality Toolkit

Describe the bug
When you say "select" on Windows MR, the MRTK input system should fire an input down and input up for the "select" action.

This is a regression, as it previously worked when we were listening for the InteractionManager's events, as voice comes across as events but not as an actual "state". Now that #2890 moved away from eventing to polling, the "select" voice command isn't represented in the InteractionManager's states.

To Reproduce
Steps to reproduce the behavior:

1. Add an input handler to the scene, responding the the Select event.
2. Gaze at the input handler and say "select".

Expected: the handler responds
Actual: the handler doesn't respond because no event is fired

Mixed Reality Toolkit Release Version
MRTK Beta and latest mrtk_development

[Yoyozilla]

kurtis has two fixes he is exploring.

[NorbertNemec]

I came across this issue in my attempt to fix the air-tap in Holographic Remoting. IIRC, my original approach to fix that issue would actually have accepted verbal "Select" commands as well:
https://github.com/NorbertNemec/MixedRealityToolkit-Unity/tree/experimental-input-select-fix
Please have a critical look -- the patch as it is should not be used since it will have side effects, but it might still help inspiring a solution.