Summary

Small typo where the example is missing s in -custom-generated-manifest-dir text in -help screen.

Environment

All supported

Steps to reproduce

1. kn workflow gen-manifest --help
2. Copy paste the example the parameter: kn workflow gen-manifest --custom-generated-manifest-dir=<full_directory_path>
3. Replace <full_direcotry_path> with ./test
4. Run kn workflow gen-manifest --custom-generated-manifest-dir=./test

Actual results

Error, with unrecognized command shown.

Expected results

The typos is fixed and when user follows above steps, the execution succeeds

Testing

Ensure unit tests.
Ensure procedure work.
Ensure there is a parametrization implemented in source code so that the help screens share common variable used in multiple places.