[EventDispatcher] fix doc bloc on EventDispatcherInterface
minor #12080 [EventDispatcher] fix doc bloc on EventDispatcherInterface (nicolas-grekas)

This PR was merged into the 2.3 branch.

Discussion
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[EventDispatcher] fix doc bloc on EventDispatcherInterface

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

The doc block says that an array of event names is accepted as input, but no implementation is compliant with that description.

Commits
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e3dacbd [EventDispatcher] fix doc bloc on EventDispatcherInterface