Fix header GitHub link

Author: bradp

src/components/Layout.jsx

@@ -76,7 +76,7 @@ function Header({ navigation }) {
       </div>
       <div className="relative flex justify-end ml-10 basis-0 gap-6 sm:gap-8">
         <ThemeSelector className="relative z-10" />
-        <Link href="https://github.com" className="group" aria-label="GitHub">
+        <Link href="https://github.com/MHCommunity/guide/" className="group" aria-label="GitHub">
           <svg className="w-6 h-6 fill-slate-400 group-hover:fill-slate-500 dark:group-hover:fill-slate-300" aria-hidden="true" viewBox="0 0 16 16">
             <path d="M8 0C3.58 0 0 3.58 0 8C0 11.54 2.29 14.53 5.47 15.59C5.87 15.66 6.02 15.42 6.02 15.21C6.02 15.02 6.01 14.39 6.01 13.72C4 14.09 3.48 13.23 3.32 12.78C3.23 12.55 2.84 11.84 2.5 11.65C2.22 11.5 1.82 11.13 2.49 11.12C3.12 11.11 3.57 11.7 3.72 11.94C4.44 13.15 5.59 12.81 6.05 12.6C6.12 12.08 6.33 11.73 6.56 11.53C4.78 11.33 2.92 10.64 2.92 7.58C2.92 6.71 3.23 5.99 3.74 5.43C3.66 5.23 3.38 4.41 3.82 3.31C3.82 3.31 4.49 3.1 6.02 4.13C6.66 3.95 7.34 3.86 8.02 3.86C8.7 3.86 9.38 3.95 10.02 4.13C11.55 3.09 12.22 3.31 12.22 3.31C12.66 4.41 12.38 5.23 12.3 5.43C12.81 5.99 13.12 6.7 13.12 7.58C13.12 10.65 11.25 11.33 9.47 11.53C9.76 11.78 10.01 12.26 10.01 13.01C10.01 14.08 10 14.94 10 15.21C10 15.42 10.15 15.67 10.55 15.59C13.71 14.53 16 11.53 16 8C16 3.58 12.42 0 8 0Z" />
           </svg>