Fix a regression where Updatecli doesn't detect anymore if the udash config file exist.
errors.Is(err, fs.ErrNotExist) supersede os.IsNotExist(err)

The last one only check if the error is is not exist while the first function checks if err contain is not exist

Test

To test this pull request, you can run the following commands:

cd <to_package_directory>
go test

Additional Information

Checklist

• I have updated the documentation via pull request in website repository.

Tradeoff

Potential improvement