add check for skills folder

Signed-off-by: YanxuanLiu <yanxuanl@nvidia.com>

Author: YanxuanLiu

.github/workflows/license-header-check.yml

@@ -54,7 +54,7 @@ jobs:
             *.ini,
             *.java,
             *.fbs,
-            skills/*/SKILL.md
+            skills/*
           excluded_file_patterns: |
             *target/*,
             thirdparty/*,