chore: release datastore 1.6.0 (#4416)

Co-authored-by: Christopher Wilcox <crwilcox@google.com>
diff --git a/datastore/CHANGES.md b/datastore/CHANGES.md
index d25e9a6..7af40ab 100644
--- a/datastore/CHANGES.md
+++ b/datastore/CHANGES.md
@@ -1,5 +1,17 @@
 # Changes
 
+## [1.6.0](https://www.github.com/googleapis/google-cloud-go/compare/datastore/v1.5.0...datastore/v1.6.0) (2021-09-17)
+
+
+### Features
+
+* **datastore/admin:** Publish message definitions for new Cloud Datastore migration logging steps. ([528ffc9](https://www.github.com/googleapis/google-cloud-go/commit/528ffc9bd63090129a8b1355cd31273f8c23e34c))
+
+
+### Bug Fixes
+
+* **datastore:** Initialize commit sentinel to avoid cross use of commits ([#4599](https://www.github.com/googleapis/google-cloud-go/issues/4599)) ([fcf13b0](https://www.github.com/googleapis/google-cloud-go/commit/fcf13b0abad4f837d4f4f53fad6c55eba1a0fe56))
+
 ## [1.5.0](https://www.github.com/googleapis/google-cloud-go/compare/v1.4.0...v1.5.0) (2021-03-01)