ccanlint: fix score for info_summary_single_line

My refactoring introduced a bug: we need to set score=1 for the success case.

tools/ccanlint/tests/info_summary_single_line.c

@@ -13,6 +13,8 @@ static void check_info_summary_single_line(struct manifest *m,
 	struct doc_section *d;
 
 	score->pass = true;
+	score->score = 1;
+
 	list_for_each(infodocs, d, list) {
 		const char *after;