Fix unit tests (mostly

Signed-off-by: Joas Schilling <coding@schilljs.com>

Author: nickvergessen

tests/OperationTest.php

@@ -34,6 +34,10 @@
 use OCP\WorkflowEngine\IRuleMatcher;
 use PHPUnit\Framework\MockObject\MockObject;
 use Test\TestCase;
+use OCP\SystemTag\ISystemTagObjectMapper;
+use OCP\SystemTag\ISystemTagManager;
+use OCP\IL10N;
+use OCP\WorkflowEngine\IManager;
 
 class OperationTest extends TestCase {