OpenXR plugin crashes Unity on play with no Oculus connected but OVR service running

### To replicate:
1. Configure Unity Project Settings to use OpenXR:
- "[...] > XR Plug-in Management > Initialize XR on Startup": Yes
- "[...] > XR Plug-in Management >Plug-in Providers": OpenXR (Oculus is unchecked and grayed out)
- "[...] > XR Plug-in Management > OpenXR > OpenXR Feature Groups > All Features > OculusXR Feature": Yes
2. Open the Oculus companion app
3. Ensure no VR headset is connected.
4. Press "Play" in Unity (you don't even need a rig in your scene)
5. **crash**

### More information:
Note that this crash does not happen if the OVR service is not running.
If OculusXR Feature is off when pressing "play" in Unity, but subsequently turned on afterward through the popup that appears, it won't crash. (but of course will crash if you press "play" again is it is now turned on)

### Versions:
OpenXR Plugin: 1.6.0 · December 01, 2022
Unity: 2022.2.3f1
Oculus App Version 47.0.0.286.341 (47.0.0.286.341)

### Logs:
[Editor.log](https://github.com/KhronosGroup/OpenXR-SDK-Source/files/10504356/Editor.log)
[crash.dmp.txt](https://github.com/KhronosGroup/OpenXR-SDK-Source/files/10504358/crash.dmp.txt) (remove `.txt` extension)
Crash window:
```
Obtained 2 stack frames
RtlLookupFunctionEntry returned NULL function. Aborting stack walk.

```

Reproduce the crash in Unity 2022.2.3f1 with OpenXR and the OculusXR Feature enabled while the Oculus service runs without a headset. Start by reviewing Editor.log and crash.dmp.txt, then trace the plugin startup path implicated by the crash. Done means pressing Play no longer crashes under these conditions.

Written by the indexing model from the issue text.