deleting the build folder to get a fresh rebuild

jobscript/build.sh

@@ -23,6 +23,7 @@ git pull
 # pip install --upgrade pip setuptools wheel jinja2 py-cpuinfo lbmpy pystencils
 # pip list
 
+[ -d "${BUILD_DIR}" ] && rm -rf ${BUILD_DIR}
 mkdir -p ${BUILD_DIR}
 cd ${BUILD_DIR}