feat: delete keycloak user when deleting user entity

[tomwwinter]

closes: https://github.com/Aam-Digital/ndb-core/issues/1874

Visible/Frontend Changes

• [ ] show warning popup, when keycloak user could not removed after user deletion

Architectural/Backend Changes

• [ ] see https://github.com/Aam-Digital/account-backend/pull/38

[github-actions[bot]]

Deployed to https://pr-2514.aam-digital.net/

[aam-digital-ci]

:tada: This PR is included in version 3.41.0-master.1 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket:

[aam-digital-ci]

:tada: This PR is included in version 3.41.0 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: