Remove duplicate bug in CHANGELOG.md
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ef90a59..b6bb9ee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -93,7 +93,7 @@
* Fix wrong alpha plane deallocation when decoded tile pixel format does not
match reconstructed output image pixel format (b/320234262).
* Fix identical chunk skipping optimization when writing animation data
- (b/321189607 and b/321189607).
+ (b/321189607).
* Fix ID selection for artificial grid alpha item when decoding a grid of tiles
which each have an associated auxiliary alpha image item
(https://crbug.com/oss-fuzz/65657).
