Preserve blank lines

[jayqi]

Fixes #5.

[github-actions]

🚀 Deployed on https://deploy-preview-7--amazing-lalande-093786.netlify.app

[codecov-io]

Codecov Report

Merging #7 (77636d0) into main (376cb47) will decrease coverage by 0.6%.
The diff coverage is 75.0%.

@@           Coverage Diff           @@
##            main      #7     +/-   ##
=======================================
- Coverage   90.6%   90.0%   -0.7%     
=======================================
  Files          6       6             
  Lines        258     260      +2     
=======================================
  Hits         234     234             
- Misses        24      26      +2     

Impacted Files	Coverage Δ
reprexlite/code.py	73.9% <75.0%> (+0.7%)	⬆️
reprexlite/version.py	80.0% <0.0%> (-20.0%)	⬇️
reprexlite/session_info.py	94.7% <0.0%> (-2.7%)	⬇️