Summary:
`strlen()` was used in Phabricator to check if a generic value is a non-empty string.
This behavior is deprecated since PHP 8.1. Phorge adopts `phutil_nonempty_string()` as a replacement.
Note: this may highlight other absurd input values that might be worth correcting
instead of just ignoring. If phutil_nonempty_string() throws an exception in your
instance, report it to Phorge to evaluate and fix that specific corner case.
```
ERROR 8192: strlen(): Passing null to parameter #1 ($string) of type string is deprecated at [/var/www/html/phorge/phorge/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldInt.php:56]
```
Closes T15685
Test Plan: After configuring a custom `int` field and a dashboard panel to query and listed the latest created tasks, access the panel and check the PHP error log.
Reviewers: O1 Blessed Committers, speck, valerio.bozzolan
Reviewed By: O1 Blessed Committers, speck, valerio.bozzolan
Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Maniphest Tasks: T15685
Differential Revision: https://we.phorge.it/D25489
052b5f41c7