fix(Hooks): Don't use offset null as it's deprecated (and not actually used)

Signed-off-by: Joas Schilling <[email protected]>

Author: nickvergessen

tests/lib/Files/ViewTest.php

@@ -1817,7 +1817,7 @@ public static function basicOperationProviderForLocks(): array {
 				'stat',
 				['dir'],
 				'dir',
-				null,
+				'',
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,
@@ -1828,7 +1828,7 @@ public static function basicOperationProviderForLocks(): array {
 				'filetype',
 				['dir'],
 				'dir',
-				null,
+				'',
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,
@@ -1857,7 +1857,7 @@ public static function basicOperationProviderForLocks(): array {
 				'filemtime',
 				['dir'],
 				'dir',
-				null,
+				'',
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,
 				ILockingProvider::LOCK_SHARED,