Docs: update CHANGELOG on v0.9.28 (#4010)

- Adds changes made since `CHANGELOG.md` was last updated.

CHANGELOG.md

@@ -13,9 +13,18 @@
 * Fix [#3963](https://github.com/buefy/buefy/issues/3963) No dropdown showed up if the data array was empty and only the footer slot was registered (thanks @GMartigny)
 * Fix [#3971](https://github.com/buefy/buefy/issues/3971) Problems with table headers and dates due to 0.9.25 → 0.9.27 changes
 * Fix [#3971](https://github.com/buefy/buefy/issues/3971) Percentage width on table columns doubly applied
-* Fix [#3991](https://github.com/buefy/buefy/pull/3991) Potential call after unmount in `NumberInput` (thanks @Arooba-git)
-* Fix [#3991](https://github.com/buefy/buefy/pull/3991) Potential call after unmount in `Sidebar` (thanks @Arooba-git)
+* Fix [#3991](https://github.com/buefy/buefy/pull/3991) Potential call after unmount in the following components (thanks @Arooba-git):
+  * `NumberInput`
+  * `Sidebar`
 * Fix [#3991](https://github.com/buefy/buefy/pull/3991) Potential listener leaks in `SliderThumb` (thanks @Arooba-git)
+* Fix [#4000](https://github.com/buefy/buefy/pull/4000) Potential call after unmount in the following components (thanks @Arooba-git):
+  * `Autocomplete`
+  * `ColorpickerHSLRepresentationSquare`
+  * `ColorpickerHSLRepresentationTriangle`
+  * `Dropdown`
+  * `Slider`
+  * `Taginput`
+  * `Tooltip`
 
 ## 0.9.27