The absolute new location of:
C:\Users<user>\Documents\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
in 4.17 is at:
C:\Program Files\Epic Games\UE_4.17\Engine\Saved\UnrealBuildTool
Well atleast on my pc 
Cheers,
RJ
Cheers,
The absolute new location of:
C:\Users<user>\Documents\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
in 4.17 is at:
C:\Program Files\Epic Games\UE_4.17\Engine\Saved\UnrealBuildTool
Well atleast on my pc
RJ