Add 1.5.x changelog (unicode-org#5004)

sffc · sffc · commit c892e80e4dcc · 2024-06-06T08:50:30.000-07:00
unicode-org#4977 (cherry picked from commit fe96085)
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## icu4x 1.5.x
+
+- `icu_datetime`
+  - Fix incorrect assertion in week-of-year formatting (https://github.com/unicode-org/icu4x/issues/4977)
+
 ## icu4x 1.5 (May 28, 2024)
 
 - Components
