fix: add content-length to 301 response

If the root URL is missing the trailing /, roundup-server returns a
301 redirect with the trailing /. However it was missing the
content-length that allows the client to handle the response and
redirect and reuse the connection (for http 1.1).

Author: rouilj

roundup/scripts/roundup_server.py

@@ -405,6 +405,7 @@ def inner_run_cgi(self):
             if query:
                 url += '?' + query
             self.send_header('Location', url)
+            self.send_header('Content-Length', 17)
             self.end_headers()
             self.wfile.write(b'Moved Permanently')
             return