Don't discard empty lines in @BeginCode blocks

[fingolfin]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.83%. Comparing base (4b0816a) to head (2571c52).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #292      +/-   ##
==========================================
+ Coverage   81.72%   81.83%   +0.10%     
==========================================
  Files          13       13              
  Lines        2161     2174      +13     
==========================================
+ Hits         1766     1779      +13     
  Misses        395      395              

Files with missing lines	Coverage Δ
gap/DocumentationTree.gd	100.00% <100.00%> (ø)
gap/DocumentationTree.gi	92.82% <100.00%> (+0.22%)	⬆️
gap/Parser.gi	72.64% <100.00%> (ø)

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[fingolfin]

Apologies to GitHub user @BeginCode for accidentally tagging them here (I've fixed that now and am deliberately not tagging you again, but posting this here just in case you are reading this because your notifications lead you here)