Improvements needed:
Remove extra space of the end of lines.
https://forge.softwareheritage.org/source/swh-lister/browse/master/docs/run_a_new_lister.rst$33
Add the exact location of `conf/lister.yml` file
https://forge.softwareheritage.org/source/swh-lister/browse/master/docs/run_a_new_lister.rst$50-51
Fix typos in this line