Update instructions for enabling javascript when javascript is disabled

When a user with javascript disabled is visiting https://metrics.torproject.org/rs.html#search they can see the following text: Please enable JavaScript to use this service. If you are using Tor Browser on High Security mode, it is possible to enable JavaScript to run only on this page. Click the NoScript icon on your address bar and select "Temporarily allow all on this page". Relay Search only uses JavaScript resources that are hosted by the Tor Metrics team.

However in recent versions of Tor Browser, there is no NoScript button in the address bar by default.