Sort imports from all files

Add "prettier" script in `package.json` to check if all files are
compliant.

Sort all imports and format all files by running `npm run lint -- --fix`
followed by `npm run prettier -- --write`.

Gitlab #29

Change-Id: Id80402d1344c3bc611f66a46cffeee5f2c375bd8
diff --git a/client/src/pages/serverConfiguration.jsx b/client/src/pages/serverConfiguration.jsx
index 8ac85df..da6250a 100644
--- a/client/src/pages/serverConfiguration.jsx
+++ b/client/src/pages/serverConfiguration.jsx
@@ -1,9 +1,10 @@
-import Header from '../components/Header';
-import AccountPreferences from '../components/AccountPreferences';
-import Container from '@mui/material/Container';
 import CircularProgress from '@mui/material/CircularProgress';
-import authManager from '../AuthManager';
+import Container from '@mui/material/Container';
+
 import Account from '../../../model/Account';
+import authManager from '../AuthManager';
+import AccountPreferences from '../components/AccountPreferences';
+import Header from '../components/Header';
 
 const ServerOverview = (props) => {
   this.accountId = props.accountId || props.match.params.accountId;