[duneproject] fix generated config.h.cmake

add missing @

bin/duneproject

@@ -552,7 +552,7 @@ cat> "$PROJECT/config.h.cmake" <<EOF
 
 /* begin private */
 /* Name of package */
-#define PACKAGE "@DUNE_MOD_NAME"
+#define PACKAGE "@DUNE_MOD_NAME@"
 
 /* Define to the address where bug reports for this package should be sent. */
 #define PACKAGE_BUGREPORT "@DUNE_MAINTAINER@"