[EventDispatcher] Delay instantiation of a service until the respective listener is triggered in ContainerAwareEventDispatcher

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #12007
| License       | MIT
| Doc PR        | no
IMO, you should not have these getters once you add the method returning the callable