Steps to reproduce:
1. Open the attached user project "VRMipMaps.zip"
2. Build and run the player on Quest 2
3. Observe the test Texture changing

Expected results: Texture is affected by VR resolution, not by the screen resolution
Actual results: Texture is affected by screen resolution, not VR resolution

Reproducible with: 2021.3.30f1, 2022.3.8f1, 2023.1.10f1, 2023.2.0b7, 2023.3.0a3

Reproducible on: Windows 10 2H22
Not reproducible on: No other environment tested

Notes:
-Tested with both OpenXR and OculusXR plugins
-When deploying to Quest, the 1D backbuffer is still created, but not used. To reduce the impact of this, Screen.SetResolution is used to decrease the size. When setting the Screen resolution to a reduced resolution, the calculated mipmap level is affected, reducing the quality of these Textures.
-Issue is not reproducible on a Non VR Standalone player