The subtarget to build. (optional)
For certain platforms, setting a non-zero value for this property can modify the build behaviour.
Both this property and BuildAssetBundlesParameters.targetPlatform should remain unset to automatically use the target and subtarget as defined in the current Build Profile.
The valid values for this property correspond to target-specific enums, which are cast to ints. Examples of these enums include StandaloneBuildSubtarget, MobileTextureSubtarget and WebGLTextureSubtarget.
Usage examples:
Additional resources: BuildPlayerOptions.subtarget, EditorUserBuildSettings.standaloneBuildSubtarget, EditorUserBuildSettings.androidBuildSubtarget, EditorUserBuildSettings.webGLBuildSubtarget.