Update CHANGELOG for 2.1.0 (#440)

Author: aaronchung-bitquill

CHANGELOG.md

@@ -3,6 +3,27 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/#semantic-versioning-200).
 
+## [2.1.0] - 2023-5-11
+### :magic_wand: Added
+- `AuroraHostListProvider` to check for stale writer records obtained after writer-failover so that they are not used ([PR #435](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/435)).
+
+### :bug: Fixed
+- Potential security concern by ensuring that user specific connections in the connection pool are returned to the correct user ([PR #432](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/432)).
+- Connection state transfer bug where switching from read-only connection to writer connection incorrectly triggers the failover process ([Issue #426](https://github.com/awslabs/aws-advanced-jdbc-wrapper/issues/426)).
+- Incorrect invalidation of newly promoted writer and random readers after failover. EFM plugin to use instance endpoint as the monitoring endpoint in the case the initial connection is established using cluster endpoint ([PR #431](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/431)).
+- Running Hibernate tests no longer runs unrelated tests ([PR #417](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/417)).
+- Reader failover using shared Properties object resulting in race conditions ([PR #436](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/436) & [PR #438](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/438)).
+- Temporarily set socket timeout for the topology query if it is not set, to avoid topology query from executing indefinitely ([PR #416](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/416)).
+
+### :crab: Changed
+- Removed logic that changes connection to a writer instance when `setReadOnly(false)` is called on a reader connection ([Issue #426](https://github.com/awslabs/aws-advanced-jdbc-wrapper/issues/426)).
+- Removed Multi-writer cluster related code as they are no longer supported ([PR #435](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/435)).
+- Clarified documentation on failover process to account for Aurora PostgerSQL clusters being offline during failover ([PR #437](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/437)).
+- :warning: Breaking changes were introduced with the new `failoverMode` configuration parameter ([PR #434](https://github.com/awslabs/aws-advanced-jdbc-wrapper/pull/434)):
+    - The `failoverMode` parameter replaces the `enableFailoverStrictReader` configuration parameter.
+    - If you were previously using `enableFailoverStrictReader=true`, please update it to `failoverMode=strict-reader`.
+    - For more information, please check the ([documentation](https://github.com/awslabs/aws-advanced-jdbc-wrapper/blob/main/docs/using-the-jdbc-driver/using-plugins/UsingTheFailoverPlugin.md#failover-parameters))
+
 ## [2.0.0] - 2023-04-28
 ### :magic_wand: Added
 - [Read / Write Splitting (Official Release)](https://github.com/awslabs/aws-advanced-jdbc-wrapper/blob/main/docs/using-the-jdbc-driver/using-plugins/UsingTheReadWriteSplittingPlugin.md).
@@ -75,6 +96,7 @@ The Amazon Web Services (AWS) Advanced JDBC Driver allows an application to take
 * The [AWS IAM Authentication Connection Plugin](./docs/using-the-jdbc-driver/using-plugins/UsingTheIamAuthenticationPlugin.md)
 * The [AWS Secrets Manager Connection Plugin](./docs/using-the-jdbc-driver/using-plugins/UsingTheAwsSecretsManagerPlugin.md)
 
+[2.1.0]: https://github.com/awslabs/aws-advanced-jdbc-wrapper/compare/2.0.0...2.1.0
 [2.0.0]: https://github.com/awslabs/aws-advanced-jdbc-wrapper/compare/1.0.2...2.0.0
 [1.0.2]: https://github.com/awslabs/aws-advanced-jdbc-wrapper/compare/1.0.1...1.0.2
 [1.0.1]: https://github.com/awslabs/aws-advanced-jdbc-wrapper/compare/1.0.0...1.0.1