The most up-to-date solution to include in the *.bat script is:
@"<AbsoluteEnginePath>Binaries\DotNET\UnrealBuildTool.exe" -projectfiles -project="<FullPathToUprojectFile>" -game -rocket -progress
Example:
@"C:\ProgramFiles\Epic Games\UE_4.25\Engine\Binaries\DotNET\UnrealBuildTool.exe" -projectfiles -project="C:\Projects\MyProject\MyProject.uproject" -game -rocket -progress
Important: quotation marks matter!