Sync command-line run instructions across DPS tutorial and the README.md in this repo

[rtapella]

Brian: I think the last step here should include an example bash command that contains arguments (e.g. bash ${path_to_repo_parent_dir}/dps_tutorial/gdal_wrapper/run_gdal.sh "test.jpg" "100")

I see there are more detailed instructions in the docs but I found myself unsure of which doc was the right place to follow. Maybe bring them in sync or link back to the more detailed docs page which is more thorough than the README in the repo.