Set default port for CURRICULUM_AUTOMATION_API_URL

[sentry]

Observed behavior

Infrastructure is not declaring the port in the env var that we use for connecting to the CA API. Since Infra does have control over what this port is in production, they will be updating the env var to contain the port.

Expected behavior

Despite infrastructure updating their side to pass the port, we should set a default port that is used if the CURRICULUM_AUTOMATION_API_URL Django setting does not have an explicit port defined. In the below instance, this would prevent it from attempting the default 80 which we rarely use.

Issue

Sentry Issue: STUDIO-HSW

TimeoutError: timed out
  File "urllib3/connection.py", line 174, in _new_conn
    conn = connection.create_connection(
  File "urllib3/util/connection.py", line 95, in create_connection
    raise err
  File "urllib3/util/connection.py", line 85, in create_connection
    sock.connect(sa)

ConnectTimeoutError: (<urllib3.connection.HTTPConnection object at 0x7ec7921320b0>, 'Connection to 10.128.15.193 timed out. (connect timeout=5)')
(5 additional frame(s) were not displayed)
...
  File "http/client.py", line 1278, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "http/client.py", line 1038, in _send_output
    self.send(msg)
  File "http/client.py", line 976, in send
    self.connect()
  File "urllib3/connection.py", line 205, in connect
    conn = self._new_conn()
  File "urllib3/connection.py", line 179, in _new_conn
    raise ConnectTimeoutError(

MaxRetryError: HTTPConnectionPool(host='10.128.15.193', port=80): Max retries exceeded with url: /stable/connect (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7ec7921320b0>, 'Connection to 10.128.15.193 timed out. (connect timeout=5)'))
  File "requests/adapters.py", line 667, in send
    resp = conn.urlopen(
  File "urllib3/connectionpool.py", line 827, in urlopen
    return self.urlopen(
  File "urllib3/connectionpool.py", line 799, in urlopen
    retries = retries.increment(
  File "urllib3/util/retry.py", line 592, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))

ConnectTimeout: HTTPConnectionPool(host='10.128.15.193', port=80): Max retries exceeded with url: /stable/connect (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7ec7921320b0>, 'Connection to 10.128.15.193 timed out. (connect timeout=5)'))
  File "automation/utils/appnexus/base.py", line 112, in _make_request
    response = self.session.request(
  File "automation/utils/appnexus/base.py", line 30, in request
    return super().request(*args, **kwargs)

HTTPConnectionPool(host='10.128.15.193', port=80): Max retries exceeded with url: /stable/connect (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7ec7921320b0>, 'Connection to 10.128.15.193 timed out. (connect timeout=5)'))

References

#5041
#5056