[BUGFIX] Check Notification action prior to execution

The Notification JavaScript module previously
failed to check a given action before executing
it. This is now fixed with an "instance of" check.

Resolves: #95406
Releases: master
Change-Id: I4a620d42f822baa1a54a441281e9291af4649d29
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/71379


Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Benni Mack <benni@typo3.org>