[TASK] Make the `NoopEventDispatcher` available to extensions

With the class moved out of the `Tests` namespace into the general
`EventDispatcher` namespace, extensions can now also use this class
for their tests.

Also add unit tests for the moved class.

Resolves: #99070
Releases: main, 11.5
Change-Id: I69b94f50f68dcacfe036e8eb489ba6b82fbb585a
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76569


Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>