Revert "Tasks: add license to files"

Depends on a completely broken piece of code.

This reverts commit 75f2b50a29.

src/components/Tasks/QuickAdd.tsx

@@ -1,6 +1,3 @@
-// SPDX-FileCopyrightText: © 2017 EteSync Authors
-// SPDX-License-Identifier: AGPL-3.0-only
-
 import * as React from 'react';
 
 import * as EteSync from 'etesync';

src/components/Tasks/TaskListItem.tsx

@@ -1,6 +1,3 @@
-// SPDX-FileCopyrightText: © 2017 EteSync Authors
-// SPDX-License-Identifier: AGPL-3.0-only
-
 import * as React from 'react';
 
 import { TaskType } from '../../pim-types';