Update CHANGELOG.md

Author: harsharahul

CHANGELOG.md

@@ -3,6 +3,10 @@ All notable changes to this project will be documented in this file.
 
 See [DocuSign Support Center](https://support.docusign.com/en/releasenotes/) for Product Release Notes.
 
-## [v1.0.0a0] - OrgAdmin API v2.0-1.0.2 - 2020-06-07
+## [v1.0.0b0] - Admin API 1.0.0b3-v2.1-1.0.0 - 2020-07-30
 ### Added
-- First Alpha version of OrgAdmin API, supports DocuSign OrgAdmin
+- First Beta version of Admin API, supports DocuSign Admin
+
+## [v1.0.0a0] - Admin API v2.0-1.0.2 - 2020-06-07
+### Added
+- First Alpha version of Admin API, supports DocuSign Admin