add changelog entry

Author: Michael Büßemeyer

CHANGELOG.unreleased.md

@@ -21,6 +21,7 @@ For upgrade instructions, please check the [migration guide](MIGRATIONS.released
 
 ### Fixed
 - Fixed that listing datasets with the `api/datasets` route without compression failed due to missing permissions regarding public datasets. [#8249](https://github.com/scalableminds/webknossos/pull/8249)
+- Fixed a bug that uploading a zarr dataset with an already existing `datasource-properties.json` file failed. [#8268](https://github.com/scalableminds/webknossos/pull/8268)
 - Fixed that the frontend did not ensure a minium length for annotation layer names. Moreover, names starting with a `.` are also disallowed now. [#8244](https://github.com/scalableminds/webknossos/pull/8244)
 - Fixed a bug where in the add remote dataset view the dataset name setting was not in sync with the datasource setting of the advanced tab making the form not submittable. [#8245](https://github.com/scalableminds/webknossos/pull/8245)
 - Fix read and update dataset route for versions 8 and lower. [#8263](https://github.com/scalableminds/webknossos/pull/8263)