Nginx: remove /development redirects on Docs site

These were set up to redirect the original locations of the development
pages to their new locations inside the instructions folder, but can't
be used any more now that we're creating a development folder.

salt/salt/nginx/tildes-static-sites.conf.jinja2

@@ -23,14 +23,6 @@ server {
         return 302 https://docs.tildes.net/policies/code-of-conduct;
     }
 
-    location /development {
-        return 302 https://docs.tildes.net/instructions/development;
-    }
-
-    location /development-setup {
-        return 302 https://docs.tildes.net/instructions/development-setup;
-    }
-
     location /mechanics {
         return 302 https://docs.tildes.net/instructions;
     }