Add README link to .asf.yaml

.asf.yaml

diff --git a/.asf.yaml b/.asf.yaml
index c761337..c717a59 100644
--- a/.asf.yaml
+++ b/.asf.yaml
@@ -1,3 +1,5 @@
+# https://github.com/apache/infrastructure-asfyaml/blob/main/README.md
+
 notifications:
   issues: notifications@community.apache.org