v0.28.2

build: Bump version 0.28.2 (#3635)

* feat: Datamodel cb signature for various events (#3624)

* feat: Datamodel cb for add_on_child_created

* feat: datamodel cbs for other events

* feat: type hint

* feat: add_on_changed

* feat: type hint

* feat: Registration method signature is changed

* test: fix

* build: Bump version 0.28.2

* fix: test