Update dawidd6/action-send-mail action to v23

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/announce-lts-rc.yml

@@ -17,7 +17,7 @@ jobs:
           discourse-author-username: jenkins-release-bot
           discourse-category: 23
       - name: Post on mailing list
-        uses: dawidd6/action-send-mail@67ce3558d613188179559c61d3565140cf389968 # v22
+        uses: dawidd6/action-send-mail@47af4a10b540781705f283a2cf1a9650713ac795 # v23
         with:
           server_address: smtp.gmail.com
           server_port: 465