Merge branch 'bug/doku/graphviz' into 'developer'

Checks if Graphviz is in PATH

See merge request !73
4 jobs for developer in 4 minutes and 40 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Preprocessing
passed #238617
linting

00:01:04

 
  Testing
passed #238618
test

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  Documentation
passed #238619
coverage

00:01:03

97.0%
passed #238620
pages

00:01:17