This is an automated cherry-pick of pingcap#20347

Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>

Author: qiancai

TOC.md

@@ -1018,6 +1018,7 @@
   - v6.6
     - [6.6.0-DMR](/releases/release-6.6.0.md)
   - v6.5
+    - [6.5.12](/releases/release-6.5.12.md)
     - [6.5.11](/releases/release-6.5.11.md)
     - [6.5.10](/releases/release-6.5.10.md)
     - [6.5.9](/releases/release-6.5.9.md)