gz-rendering9+: build without -DSKIP_optix (#1161)

Signed-off-by: Steve Peters <scpeters@openrobotics.org>

jenkins-scripts/docker/gz_rendering-compilation.bash

@@ -35,6 +35,10 @@ fi
 export GPU_SUPPORT_NEEDED=true
 export GZDEV_PROJECT_NAME="gz-rendering${GZ_RENDERING_MAJOR_VERSION}"
 
-export BUILDING_EXTRA_CMAKE_PARAMS+=" -DSKIP_optix=true"
+# set SKIP_optix=true for Harmonic and earlier
+# not needed for ionic since https://github.com/gazebosim/gz-rendering/pull/1032
+if [[ ${GZ_RENDERING_MAJOR_VERSION} -le 8 ]]; then
+  export BUILDING_EXTRA_CMAKE_PARAMS+=" -DSKIP_optix=true"
+fi
 
 . ${SCRIPT_DIR}/lib/generic-building-base.bash