ci: another pass at getting OpenSCAD working

Author: EmperorArthur

.github/workflows/ci.yml

@@ -45,6 +45,7 @@ jobs:
       run: |
         sudo apt-get update
         sudo apt-get install openscad
+        sudo apt-get install xvfb
 
     - name: OpenSCAD Build Information
       run: openscad --info

tests/openscad_runner.py

@@ -117,7 +117,7 @@ class OpenScadRunner:
         #'--hardwarnings', # Does not work when setting variables by using functions
         #'--enable=fast-csg', # Requires Beta version of OpenSCAD
         #'--enable=predictible-output', # Requires Beta version of OpenSCAD
-        '--render=true'  # Required on headless systems
+        #'--render=true'  # Fully render geometry for images, instead of using fast preview mode.
         '--imgsize=1280,720',
         '--view=axes',
         '--projection=ortho',