Remove react-intl due failing tests

The dependency requires to inject provider for test. To evalue another
library for intl

src/index.tsx

 import React from 'react';
 import ReactDOM from 'react-dom';
-import { IntlProvider } from 'react-intl';
 import CssBaseline from '@material-ui/core/CssBaseline';
-import MESSAGES_EN from './intl/en.json';
 import { App } from './App';
 
 ReactDOM.render(
   <React.StrictMode>
-    <IntlProvider locale="en" messages={MESSAGES_EN}>
-      <CssBaseline />
-      <App />
-    </IntlProvider>
-    ,
+    <CssBaseline />
+    <App />,
   </React.StrictMode>,
   document.getElementById('root'),
 );

src/intl/en.json

-{
-    "email": "Email address",
-    "password": "Password",
-    "email-error": "Insert valid email address",
-    "password-error": "Insert valid password"
-}
\ No newline at end of file