fix: unit test

Signed-off-by: Vitor Mattos <vitor@php.rio>

Author: vitormattos

tests/Unit/Service/SignFileServiceTest.php

@@ -187,6 +187,8 @@ public function testSignWithFileNotFound():void {
 		$file = new \OCA\Libresign\Db\File();
 		$file->setUserId('username');
 
+		$this->root->method('getUserFolder')
+			->willReturn($this->root);
 		$this->root->method('getById')
 			->willReturn([]);
 		$this->userMountCache
@@ -217,6 +219,7 @@ public function testSignWithSuccess(string $mimetype, string $filename, string $
 		$nextcloudFile->method('getContent')->willReturn('fake content');
 		$nextcloudFile->method('getId')->willReturn(171);
 
+		$this->root->method('getUserFolder')->willReturn($this->root);
 		$this->root->method('getById')->willReturn([$nextcloudFile]);
 		$this->root->method('newFile')->willReturn($nextcloudFile);
 		$this->userMountCache->method('getMountsForFileId')->wilLReturn([]);