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/redux/store.ts b/client/redux/store.ts
index f6ab51d..3c67034 100644
--- a/client/redux/store.ts
+++ b/client/redux/store.ts
@@ -1,4 +1,5 @@
 import { configureStore } from '@reduxjs/toolkit';
+
 import appReducer from './appSlice';
 
 export const store = configureStore({