SRVCOM-2767 Update _distro_map.yml

Author: briandooley

_distro_map.yml

@@ -309,6 +309,9 @@ openshift-serverless:
     serverless-docs-1.30:
       name: '1.30'
       dir: serverless/1.30
+    serverless-docs-1.31:
+      name: '1.31'
+      dir: serverless/1.31
 openshift-gitops:
   name: Red Hat OpenShift GitOps
   author: OpenShift documentation team <openshift-docs@redhat.com>