📝 Document improved normalize helper in CHANGELOG.md

Signed-off-by: Peter Boling <peter.boling@gmail.com>

Author: pboling

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Added CODE_OF_CONDUCT.md (#217, #218 by @pboling)
 * Added FUNDING.yml (#217, #218 by @pboling)
 * Added Client Certificate Options: :ssl_client_cert and :ssl_client_key (#136, #220 by @pboling)
+* Handle a nested array of hashes in OAuth::Helper.normalize (#80, #221 by @pboling)
 
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