Feature/enforce license notice in each file via eslint rule (#304)

* [ESLint] Add "eslint-plugin-header" as dev dependency

* [ESLint::eslint-plugin-header] Setup rule

* [ESLint::eslint-plugin-header] Fix errors

src/components/library/LibraryOptionsPanel.tsx

@@ -3,7 +3,8 @@
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
 
 import { FormLabel, RadioGroup } from '@mui/material';
 import CheckboxInput from 'components/atoms/CheckboxInput';

src/components/library/LibraryOptionsProvider.tsx

@@ -3,7 +3,8 @@
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
 
 import LibraryOptionsContext, { DefaultLibraryOptions } from 'components/context/LibraryOptionsContext';
 import React, { useMemo } from 'react';

src/components/library/LibraryToolbarMenu.tsx

@@ -3,7 +3,8 @@
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
 
 import FilterList from '@mui/icons-material/FilterList';
 import { IconButton } from '@mui/material';

src/components/library/UpdateChecker.tsx

@@ -1,3 +1,11 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
 import React, { useEffect, useState } from 'react';
 import IconButton from '@mui/material/IconButton';
 import RefreshIcon from '@mui/icons-material/Refresh';

src/components/library/useSubscription.ts

@@ -1,3 +1,11 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
 import { useEffect, useState } from 'react';
 
 const baseWebsocketUrl = JSON.parse(window.localStorage.getItem('serverBaseURL')!).replace('http', 'ws');