Patch graphviz

Doing so fixes (for now) the Phylo error.
4 jobs for adinapoli/issue-290 in 109 minutes and 12 seconds (queued for 3 minutes and 12 seconds)
latest
Status Job ID Name Coverage
  Stack
passed #10830
stack

00:06:11

 
  Cabal
passed #10831
cabal

00:42:07

 
  Bench
passed #10832
bench

00:26:41

 
  Test
passed #10833
test

00:34:11