Docs: corrected previous release notes entry (via PR kedro-org#266, r…

…elated to issue kedro-org#256. Added new release notes entry for PR kedro-org#268, related to issue kedro-org#265

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RELEASE.md

@@ -9,6 +9,7 @@
 * Documentation improvements.
 * Updated contribution process in `CONTRIBUTING.md` - added Developer Workflow.
 * Fixed a bug where `PartitionedDataSet` and `IncrementalDataSet` were not working with `s3a` or `s3n` protocol.
+* Added facility to create an isolated Kedro development environment with the help of Docker containers
 
 ## Breaking changes to the API
 * Made `invalidate_cache` method on datasets private.