Update "join us" link

Author: larleevee

layouts/partials/header.html

@@ -5,11 +5,11 @@
 	<div class="divider"></div>
 	<nav>
 		<ul>
-			<li><a href="https://www.su.nottingham.ac.uk/societies/society/hack/" class="large">JOIN US!</a></li>
+			<li><a href="https://su.nottingham.ac.uk/societies/society/hack/" class="large">JOIN US!</a></li>
 			<li><a href="/calendar">Calendar</a></li>
 			<li><a href="https://hacknotts.com/">HackNotts</a></li>
 			<li><a href="/committee">Committee</a></li>
 			<li><a href="/contact">Contact Us</a></li>
 		</ul>
 	</nav>
-</header>
+</header>