Deprecate API v2 (#7761)

* deprecate api-v2

* remove v2 test helpers

* remove unused string

test/api/v2/user/tasks/GET-tasks.test.js

@@ -1,25 +0,0 @@
-import {
-  generateUser,
-} from '../../../../helpers/api-integration/v2';
-
-describe('GET /user/tasks/', () => {
-  let user;
-
-  beforeEach(async () => {
-    return generateUser().then((_user) => {
-      user = _user;
-    });
-  });
-
-  it('gets all tasks', async () => {
-    return user.get('/user/tasks/').then((tasks) => {
-      expect(tasks).to.be.an('array');
-      expect(tasks.length).to.equal(1);
-
-      let task = tasks[0];
-      expect(task.id).to.exist;
-      expect(task.type).to.exist;
-      expect(task.text).to.exist;
-    });
-  });
-});