Plugtest 2021: MEC012 RNISNotifications HTTPConnectionPool host name concatenation with port error

When testing any notification as part of RNISNotifications test suite, the test does not connect properly to the tap plugtest server.

Rather than using the tap.plugtests.net server on port 8111... it uses a concatenation of the port and host name resulting in tap.plugtests.net8111 and tries to reach the server on port 80. This cannot be resolved and test fails:

ConnectionError: HTTPConnectionPool(host='tap.plugtests.net8111', port=80): Max retries exceeded with url: /expectation (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f1ce504ce80>: Failed to establish a new connection: [Errno -2] Name or service not known',))