Disable Themes Trac browser for root index

As we do for Plugins Trac, can we redirect `https://themes.trac.wordpress.org/browser/?$` to wordpress.org/themes/ ?

Due to the number of themes, TracTrac Trac is the place where contributors create issues for bugs or feature requests much like GitHub.https://core.trac.wordpress.org/./nginxNGINX NGINX is open source software for web serving, reverse proxying, caching, load balancing, media streaming, and more. It started out as a web server designed for maximum performance and stability. In addition to its HTTP server capabilities, NGINX can also function as a proxy server for email (IMAP, POP3, and SMTP) and a reverse proxy and load balancer for HTTP, TCP, and UDP servers. https://www.nginx.com/. 502’s (Apparently it previous crashed trac, unsure what it’s doing now other than timing out) and the upstream trac issue hasn’t been touched in years.

Diff, as per plugins.trac.wordpress.org.

--- trac.wordpress.org.conf  (revision xxxxxxx)
+++ trac.wordpress.org.conf (working copy)
@@ -341,0 +342,5 @@ server_name themes.trac.wordpress.org;
+   # Too many themes, page doesn't load.  Instead just crashes trac
+   location ~ ^/browser/?$ {
+       return 302 https://wordpress.org/themes/;
+   }
+

ref: https://meta.trac.wordpress.org/ticket/4861

#prio3