If the user runs that command "from the source code folder", i.e.
`getting-started`, docker will bind-mount getting-started to the
container's `/app`, which leads to error
`error Couldn't find a package.json file in "/app"`. It needs to bind
`getting-started/app` instead.
So, be explicit to the reader to be on the app source's directory
`getting-started/app` before running the command.
The command for bind mount doesn't run in Ubuntu if the user is not in the source code folder. At least, for me didn't work. So I specified that to prevent errors and bugs.
Signed-off-by: mikesir87 <mikesir87@gmail.com>
Imported from dockersamples/101-tutorial, removed other languages
for now, and replaced PWD references with Docker Desktop.
