Destination redshift: delete some unused files (airbytehq#35314)

Author: edgao

airbyte-cdk/java/airbyte-cdk/README.md

@@ -166,6 +166,7 @@ MavenLocal debugging steps:
 
 | Version | Date       | Pull Request                                               | Subject                                                                                                                                                        |
 |:--------|:-----------|:-----------------------------------------------------------|:---------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| 0.21.0  | 2024-02-16 | [\#35314](https://github.com/airbytehq/airbyte/pull/35314) | Delete S3StreamCopier classes. These have been superseded by the async destinations framework.                                                                 |
 | 0.20.9  | 2024-02-15 | [\#35240](https://github.com/airbytehq/airbyte/pull/35240) | Make state emission to platform inside state manager itself.                                                                                                   |
 | 0.20.8  | 2024-02-15 | [\#35285](https://github.com/airbytehq/airbyte/pull/35285) | Improve blobstore module structure.                                                                                                                            |
 | 0.20.7  | 2024-02-13 | [\#35236](https://github.com/airbytehq/airbyte/pull/35236) | output logs to files in addition to stdout when running tests                                                                                                  |

airbyte-cdk/java/airbyte-cdk/core/src/main/resources/version.properties

@@ -1 +1 @@
-version=0.20.9
+version=0.21.0