Tests: Rely on admin user, groups, permissions from test setup script

tests/integration/api/discussions/CreateTest.php

@@ -18,30 +18,6 @@ class CreateTest extends TestCase
 {
     use RetrievesAuthorizedUsers;
 
-    protected function setUp(): void
-    {
-        parent::setUp();
-
-        $this->prepareDatabase([
-            'users' => [
-                $this->adminUser(),
-                $this->normalUser(),
-            ],
-            'groups' => [
-                $this->adminGroup(),
-                $this->memberGroup(),
-            ],
-            'group_user' => [
-                ['user_id' => 1, 'group_id' => 1],
-                ['user_id' => 2, 'group_id' => 3],
-            ],
-            'group_permission' => [
-                ['permission' => 'viewDiscussions', 'group_id' => 3],
-                ['permission' => 'startDiscussion', 'group_id' => 3],
-            ]
-        ]);
-    }
-
     /**
      * @test
      */