Do not attempt to clean lock after build (only before)

gitlab/before_build.sh

@@ -21,7 +21,6 @@ if [ ! -d ${PREFIX} ]; then
   if [ "${ARCH}" == "macosx" ] && [ -e "${PREFIX}/lib/libjpeg.8.dylib" ]; then
     run_cmd install_name_tool -id @rpath/libjpeg.8.dylib ${PREFIX}/lib/libjpeg.8.dylib
   fi
-  run_cmd ${CONDA_FOLDER}/bin/conda clean --lock
 else
   log_warn "Prefix directory ${PREFIX} exists, not re-installing..."
 fi