ci: Adds libjpeg-dev dependency to sof-docs workflow

Includes libjpeg-dev in the sof docs workflow
to ensure required libraries are available for building Pillow.

Signed-off-by: Christopher Turner <christopher.g.turner@intel.com>

Author: cgturner1

.github/workflows/sof-docs.yml

@@ -39,6 +39,7 @@ jobs:
       - name: apt-get install
         run: sudo apt-get -y install
              doxygen make default-jre graphviz cmake ninja-build
+             libjpeg-dev
 
       - name: doxygen
         run: cmake -GNinja -S doc/ -B doxybuild/ && ninja -C doxybuild/ -v doc