ci: Send discussions to [email protected] (#5201)

.asf.yaml

@@ -38,12 +38,21 @@ github:
         required_approving_review_count: 1
     gh-pages:
       whatever: Just a placeholder to make it take effects
+  custom_subjects:
+    new_discussion: "[DISCUSS] {title}"
+    edit_discussion: "Re: [DISCUSS] {title}"
+    close_discussion: "Re: [DISCUSS] {title}"
+    close_discussion_with_comment: "Re: [DISCUSS] {title}"
+    reopen_discussion: "Re: [DISCUSS] {title}"
+    new_comment_discussion: "Re: [DISCUSS] {title}"
+    edit_comment_discussion: "Re: [DISCUSS] {title}"
+    delete_comment_discussion: "Re: [DISCUSS] {title}"
 
 notifications:
   commits: [email protected]
   issues: [email protected]
   pullrequests: [email protected]
-  discussions: commits@opendal.apache.org
+  discussions: dev@opendal.apache.org
 
 staging:
   profile: ~