Fix pipeline doctests
Clean PR of #17013 to fix doctests for the `pipeline` tutorial:

- Updated output values in vision example as suggested by @ydshieh.
- Fixed output format issues. Showing each output result on a new line fails :(
_The documentation is not available anymore as the PR was closed or merged._<|||||>(I don't really follow the `... ) # doctest: +SKIP`) thing. If you have a bit time, it would be great if you can explain a bit to me what issue we have previously.<|||||>Generation is random @ydshieh so the results will be different for each run. `# doctest: +SKIP` tells `doctest` to not test this particular example.