refactor: replace Spinner of Shell with the DS one

src/app.tsx

@@ -14,13 +14,13 @@ import {
 	type NewAction,
 	registerActions,
 	type SecondaryBarComponentProps,
-	Spinner,
 	useAuthenticated
 } from '@zextras/carbonio-shell-ui';
 import { useTranslation } from 'react-i18next';
 import { Route } from 'react-router-dom';
 
 import { RemindersManager } from './components/RemindersManager';
+import { Spinner } from './components/Spinner';
 import { TASKS_APP_ID, TASKS_ROUTE } from './constants';
 import { ProvidersWrapper } from './providers/ProvidersWrapper';
 

src/components/Spinner.tsx

@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2024 Zextras <https://www.zextras.com>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import React from 'react';
+
+import { Container, Spinner as SpinnerDS } from '@zextras/carbonio-design-system';
+
+export const Spinner = (): React.JSX.Element => (
+	<Container>
+		<SpinnerDS color={'primary'} />
+	</Container>
+);