Fixed link and implemented MUI

src/client/src/components/overviewbutton.js

@@ -1,10 +1,13 @@
 import React from "react";
 import { BrowserRouter as Router, Link, Route, Routes } from "react-router-dom";
+import Button from '@mui/material/Button'
 
 export default function OverviewButton(props) {
   return (
-    <button className="OverviewButton">
-      <Link to="/tournament">View Tournament</Link>
-    </button>
+    <Link to="/tournament" style={{textDecoration:'none'}}>
+      <Button className="OverviewButton">
+        View Tournament
+      </Button>
+    </Link>
   );
 }