Release ceilometer for stable/train

This release picks up new commits to ceilometer since
the last release from stable/train.

This is being proposed as a convenience to help make sure stable
changes are being released. If the team is good with this going out,
please respond with a +1 to let the release team know it is OK to
proceed.

If it is not wanted at this time, or if there are more changes that
would be good to get merged before doing a  stable release, please
leave a -1 with a comment with what the team would prefer. We can
then either abandon this patch, or wait for an update with a new
commit hash to use instead.

Signed-off-by: Elod Illes <elod.illes@est.tech>
Change-Id: I1220d32320eab262625c1c4a9a276bc077d113a1

deliverables/train/ceilometer.yaml

@@ -27,6 +27,10 @@ releases:
     projects:
       - repo: openstack/ceilometer
         hash: cad356b2104392bee869fd7b6db8bb870a650b6f
+  - version: 13.1.2
+    projects:
+      - repo: openstack/ceilometer
+        hash: 527e58bb852d3ef3a42e72691dc4a16b0e8006f8
 branches:
   - name: stable/train
     location: 13.0.0.0rc1