Add CHANGELOG.

Author: LawnGnome

CHANGELOG.md

@@ -14,6 +14,7 @@ All notable changes to `src-cli` are documented in this file.
 ### Added
 
 - `src lsif upload` now supports the `-gitlab-token` flag. [#721](https://github.com/sourcegraph/src-cli/pull/721)
+- Batch Changes can be applied to Bitbucket Cloud when `src` is used with Sourcegraph 3.40 or later. [#725](https://github.com/sourcegraph/src-cli/pull/725)
 
 ### Changed