Update CHANGELOG.md for 13.0.9

[ci skip]

CHANGELOG.md

@@ -2,6 +2,10 @@
 documentation](doc/development/changelog.md) for instructions on adding your own
 entry.
+## 13.0.9 (2020-07-06)
+
+- No changes.
+
 ## 13.0.8 (2020-07-01)
 ### Security (18 changes)