ITS#5810 undo last commit: s/^#${AC_null}#// would remove #mod#, not #nullmod#

tests/scripts/conf.sh

@@ -40,7 +40,6 @@ sed -e "s/@BACKEND@/${BACKEND}/"			\
 	-e "s/^#${BACKENDTYPE}#//"			\
 	-e "s/^#${AC_ldap}#//"				\
 	-e "s/^#${AC_meta}#//"				\
-	-e "s/^#${AC_null}#//"				\
 	-e "s/^#${AC_relay}#//"				\
 	-e "s/^#${AC_sql}#//"				\
 		-e "s/^#${RDBMS}#//"			\