GitLab

Those settings enforce convergence on common coding style with respect to whitespace.

Do not use tabs to indent with shell scripts because those tabs most often
serve the function of triggering command completion. Which could end a
command before it is pasted completely.
  Traditionally indentation is two spaces here, not four.

Other rules will catch stray whitespace at the end of lines or files, which,
once committed, would annoy the next developer because his editor would strip
them from lines he did not intended to modify in the first place.