Add PATCH/PUT request for Key Events API

[AndreiAlexandruParaschiv]

Is your feature request related to a problem? Please describe.

• When creating key events, errors in the name, type or even date can occur and there is no possibility to update/modify it.
  Nowadays, the event needs to be a) deleted and b) created again with the correct data.

Describe the solution you'd like

• Introduce the PUT request to be able to modify the name/type or date of the key event.

Describe alternatives you've considered

• PUT for endpoint /sites/{siteId}/key-events/{keyEventId}