Fix publishing site via branch (#437)


As recommended in https://issues.apache.org/jira/browse/INFRA-22028?focusedCommentId=17368241&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-17368241

diff --git a/.asf.yaml b/.asf.yaml
index eb9a68c..832ab79 100644
--- a/.asf.yaml
+++ b/.asf.yaml
@@ -36,3 +36,6 @@
         required_approving_review_count: 1
 
   ghp_branch: gh-pages
+
+publish:
+  whoami:   gh-pages