When cargo-wdk's output is redirected to a file it still writes ANSI escape sequences as shown below:
�[32m INFO�[0m Building package my-driver
�[32m INFO�[0m Copying files to target package folder: C:\Users\abc\code\my-driver\target\debug\my_driver_package
�[32m INFO�[0m Running stampinf
�[32m INFO�[0m Running inf2cat
...
Escape sequences are meant only for the console. It should skip them when redirected and the output should look like this:
INFO Building package my-driver
INFO Copying files to target package folder: C:\Users\abc\code\my-driver\target\debug\my_driver_package
INFO Running stampinf
INFO Running inf2cat
...