fix(files_external): Fix registration of listeners with PHP >= 8.4 #35302

Job	Run time
changes	9s
integration-sqlite (federation_features, 8.4, main, master)	8m 25s
integration-sqlite (capabilities_features, 8.4, main, master)	2m 40s
integration-sqlite (features, 8.4, main, master)	21m 35s
integration-sqlite (collaboration_features, 8.4, main, master)	3m 58s
integration-sqlite (openldap_numerical_features, 8.4, main, master)	2m 16s
integration-sqlite (remoteapi_features, 8.4, main, master)	2m 37s
integration-sqlite (--tags ~@large files_features, 8.4, main, master)	34m 23s
integration-sqlite (dav_features, 8.4, main, master)	13m 47s
integration-sqlite (files_reminders, 8.4, main, master)	1m 9s
integration-sqlite (openldap_features, 8.4, main, master)	3m 16s
integration-sqlite (setup_features, 8.4, main, master)	2m 30s
integration-sqlite (file_conversions, 8.4, main, master)	3m 22s
integration-sqlite (ldap_features, 8.4, main, master)	1m 38s
integration-sqlite (filesdrop_features, 8.4, main, master)	1m 44s
integration-sqlite (comments_features, 8.4, main, master)	2m 24s
integration-sqlite (sharing_features, 8.4, main, master)	28m 37s
integration-sqlite (sharees_features, 8.4, main, master)	13m 5s
integration-sqlite (videoverification_features, 8.4, main, master)	10m 0s
integration-sqlite (theming_features, 8.4, main, master)	2m 0s
integration-sqlite (routing_features, 8.4, main, master)	2m 48s
integration-sqlite-summary	5s
	2h 42m 28s

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