Use IUser

This is broken and will never work as the phan CI step pointed out.

Pro-tip of the day: Check why CI fails before merging 🙈

Signed-off-by: Lukas Reschke <lukas@statuscode.ch>

lib/private/Share20/Manager.php

@@ -42,6 +42,7 @@
 use OCP\IL10N;
 use OCP\ILogger;
 use OCP\IURLGenerator;
+use OCP\IUser;
 use OCP\IUserManager;
 use OCP\Mail\IMailer;
 use OCP\Security\IHasher;