docs: Run missing towncrier update

Author: achimnol

CHANGELOG.md

@@ -16,6 +16,16 @@ Changes
 
 .. towncrier release notes start
 
+20.09.0b3 (2020-12-21)
+----------------------
+
+
+### Features
+* Add support for hardware metadata queries for super-admins
+  - Add `admin storages` and `admin storage {vfolder-host}` commands which provides the hardware metadata and performance metric
+  - Include `hardware_metadata` field in the `Agent` graph object type. ([#152](https://github.com/lablup/backend.ai-client-py/issues/152))
+
+
 20.09.0b2 (2020-12-18)
 ----------------------