Add forgotten release note for 892427

Followup on Ief8dca4e27197c9576e215cbd960da75f6fdc20c

Related-Bug: #1879557
Change-Id: I2865fb8bb24994db8687a15fd8106bfa7a55d4da
Signed-off-by: Maksim Malchuk <maksim.malchuk@gmail.com>

releasenotes/notes/bug-designate-producers-not-running-properly-3568f9167a9547f6.yaml

+---
+fixes:
+  - |
+    Fixes an issue when Kolla is setting the producer tasks to None,
+    and this disables all designate producer tasks.
+    `LP#1879557 <https://launchpad.net/bugs/1879557>`__