docs: update change log for edit CIDR change (#285)

* docs: update change log for edit CIDR change

Update the version and date for latest release, and also updated the latest change log with remaining commits

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 All notable changes to this project will be documented in this file.
 
-## [2.0.0] - TBD
+## [2.0.0] - 2021-01-29
 
 ### Added 
 - feat: Adding ability to manage CIDR blocks of workspace's configured security group
@@ -12,6 +12,8 @@ Note:
 2. For RStudio instances, please allow 2-5 minutes for CIDR changes to take effect.
 3. For SageMaker instances, currently application admins and workspace owners have ability to access the SageMaker platform directly, irrespective of CIDR inclusion.
 
+- feat: Remove APIs for built-in workspaces
+
 ## [1.4.7] - 2021-01-28
 
 ### Added