Add Bang & Olufsen button Event entities (#127550)

* Add button events

* Remove unused common keys
Rename Preset to Favourite

* Add event testing

* Add check for Beoconnect Core

* Rename device controls

* Add test for Beoconnect core event entity creation

* Fix config entry type

* Add a type checking check before assertion

* Add icon translations

* Remove useless defined icons

* Remove base event class

* Update homeassistant/components/bang_olufsen/event.py

Co-authored-by: Josef Zweck <josef@zweck.dev>

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Co-authored-by: Josef Zweck <josef@zweck.dev>