add release note for #191

Author: TomNicholas

docs/releases.rst

@@ -23,6 +23,8 @@ Bug fixes
 
 - Fixed bug with writing of `dimension_names` into zarr metadata.
   (:pull:`286`) By `Tom Nicholas <https://github.com/TomNicholas>`_.
+- Fixed bug causing CF-compliant variables not to be identified as coordinates (:pull:`191`) 
+  By `Ayush Nag <https://github.com/ayushnag>`_.
 
 Documentation
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