Summary: Implicitly nullable parameter declarations are deprecated in PHP 8.4: https://php.watch/versions/8.4/implicitly-marking-parameter-type-nullable-deprecated The proposed syntax was introduced in PHP 7.1. This patch is a followup on top of D25814. Refs T15935 Test Plan: * Try to view a task in the browser * Try to run `./bin/auth recover` on the CLI * Try to browse projects in the browser * Try to create a new project without a name in the browser Reviewers: O1 Blessed Committers, chris Reviewed By: O1 Blessed Committers, chris Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno Maniphest Tasks: T15935 Differential Revision: https://we.phorge.it/D25816