Update gitgraph.js to fix blurry commit graph on HiDPI screens

[michaelkuhn]

The PR mentioned in #2943 has been merged, so this PR updates gitgraph.js to fix the blurry commit graph on HiDPI screens.

[codecov-io]

Codecov Report

Merging #2957 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #2957      +/-   ##
=========================================
- Coverage   26.82%   26.8%   -0.02%     
=========================================
  Files          90      90              
  Lines       17807   17807              
=========================================
- Hits         4777    4774       -3     
- Misses      12351   12353       +2     
- Partials      679     680       +1

Impacted Files	Coverage Δ
modules/process/manager.go	69.56% <0%> (-4.35%)	⬇️

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[lafriks]

LGTM

[lafriks]

@michaelkuhn could you add license comment back?

[michaelkuhn]

Sure, done! Sorry, I did not realize they were added afterwards.

[lunny]

LGTM