Calens changelog updated

Author: JuancaG05

CHANGELOG.md

@@ -1,9 +1,9 @@
-Changelog for ownCloud Android Client [unreleased] (UNRELEASED)
+Changelog for ownCloud Android Client [4.0.0] (2023-05-24)
 =======================================
-The following sections list the changes in ownCloud Android Client unreleased relevant to
+The following sections list the changes in ownCloud Android Client 4.0.0 relevant to
 ownCloud admins and users.
 
-[unreleased]: https://github.com/owncloud/android/compare/v3.0.4...master
+[4.0.0]: https://github.com/owncloud/android/compare/v3.0.4...v4.0.0
 
 Summary
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