message: docs(paper): reduce margin in the preprint
diff: @@ -217,6 +217,7 @@ paper-preprint:
  --bibliography=paper.bib \
  --variable classoption=twocolumn \
  --variable papersize=a4paper \
  + --variable geometry:margin=2cm \
  --standalone \
  --output preprint.pdf \
  paper.md
  