docs: updated CHANGELOG.md (argoproj#6821)

Signed-off-by: GitHub <[email protected]>

Co-authored-by: sarabala1979 <[email protected]>

Author: github-actions[bot]

CHANGELOG.md

@@ -243,6 +243,20 @@
  * meijin
  * wanghong230
 
+## v3.1.13 (2021-09-28)
+
+ * [78cd6918a](https://github.com/argoproj/argo-workflows/commit/78cd6918a8753a8448ed147b875588d56bd26252) fix: Missing duration metrics if controller restart (#6815)
+ * [1fe754ef1](https://github.com/argoproj/argo-workflows/commit/1fe754ef10bd95e3fe3485f67fa7e9c5523b1dea) fix: Fix expression template random errors. Fixes #6673 (#6786)
+ * [3a98174da](https://github.com/argoproj/argo-workflows/commit/3a98174dace34ffac7dd7626a253bbb1101df515) fix: Fix bugs, unable to resolve tasks aggregated outputs in dag outputs. Fixes #6684 (#6692)
+ * [6e93af099](https://github.com/argoproj/argo-workflows/commit/6e93af099d1c93d1d27fc86aba6d074d6d79cffc) fix: remove windows UNC paths from wait/init containers. Fixes #6583 (#6704)
+
+### Contributors
+
+ * Alex Collins
+ * Anish Dangi
+ * Saravanan Balasubramanian
+ * smile-luobin
+
 ## v3.1.12 (2021-09-16)
 
  * [e62b9a8dc](https://github.com/argoproj/argo-workflows/commit/e62b9a8dc8924e545d57d1f90f901fbb0b694e09) feat(ui): logsViewer use archived log if node finish and archived (#6708)