(CI) missing ghostscript dep

Src-commit: 1d07af047f6cdd8ff165a10358e383d5208fbae5

Author: jfmc

.github/workflows/build.yml

@@ -58,7 +58,7 @@ jobs:
         if: (matrix.sys.os == 'ubuntu-latest' && matrix.sys.arch == 'i686')
       # Additional setup for devenv (specially documentation generation)
       - run: |
-          sudo apt-get install emacs-nox texlive-latex-base texlive-binaries
+          sudo apt-get install emacs-nox texlive-latex-base texlive-binaries ghostscript
           sudo sed -i '/disable ghostscript format types/,+6d' /etc/ImageMagick-6/policy.xml
         if: (matrix.sys.os == 'ubuntu-latest' && matrix.sys.inskind == 'devenv')
       # Checks-out repo under $GITHUB_WORKSPACE