Fix PHP's rewrite rule in NGINX subdir example

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

Author: ChristophWurst

admin_manual/installation/nginx.rst

@@ -314,7 +314,7 @@ The configuration differs from the "Nextcloud in webroot" configuration above in
           # `/nextcloud/index.php` to the URI, resulting in a HTTP 500 error response.
           location ~ \.php(?:$|/) {
               # Required for legacy support
-              rewrite ^/(?!index|remote|public|cron|core\/ajax\/update|status|ocs\/v[12]|updater\/.+|oc[ms]-provider\/.+|.+\/richdocumentscode\/proxy) /nextcloud/index.php$request_uri;
+              rewrite ^/nextcloud/(?!index|remote|public|cron|core\/ajax\/update|status|ocs\/v[12]|updater\/.+|oc[ms]-provider\/.+|.+\/richdocumentscode\/proxy) /nextcloud/index.php$request_uri;
 
               fastcgi_split_path_info ^(.+?\.php)(/.*)$;
               set $path_info $fastcgi_path_info;