[focal] LBAASv2Test.test_create_loadbalancer fails right after floating IP creation

Seen here:

https://review.opendev.org/#/c/748652/
https://openstack-ci-reports.ubuntu.com/artifacts/test_charm_pipeline_func_full/openstack/charm-octavia/748652/1/6738/index.html

2020-08-30 17:19:27 [WARNING] A floating IP already exists but ports do not match Potentially creating more than one.
2020-08-30 17:19:27 [INFO] Creating floatingip
--2020-08-30 17:19:31-- http://172.17.112.227/
Connecting to 172.17.112.227:80... failed: Connection timed out.
Retrying.

[...]

--2020-08-30 18:02:13-- (try:20) http://172.17.112.227/
Connecting to 172.17.112.227:80... failed: Connection timed out.
Giving up.

2020-08-30 18:04:20 [INFO] ERROR
2020-08-30 18:04:20 [INFO] ======================================================================
2020-08-30 18:04:20 [INFO] ERROR: test_create_loadbalancer (zaza.openstack.charm_tests.octavia.tests.LBAASv2Test)
2020-08-30 18:04:20 [INFO] Create load balancer.
2020-08-30 18:04:20 [INFO] ----------------------------------------------------------------------
2020-08-30 18:04:20 [INFO] Traceback (most recent call last):
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/zaza/openstack/charm_tests/octavia/tests.py", line 295, in test_create_loadbalancer
2020-08-30 18:04:20 [INFO] assert snippet in self._get_payload(lb_fp['floating_ip_address'])
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/tenacity/__init__.py", line 329, in wrapped_f
2020-08-30 18:04:20 [INFO] return self.call(f, *args, **kw)
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/tenacity/__init__.py", line 409, in call
2020-08-30 18:04:20 [INFO] do = self.iter(retry_state=retry_state)
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/tenacity/__init__.py", line 368, in iter
2020-08-30 18:04:20 [INFO] raise retry_exc.reraise()
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/tenacity/__init__.py", line 186, in reraise
2020-08-30 18:04:20 [INFO] raise self.last_attempt.result()
2020-08-30 18:04:20 [INFO] File "/usr/lib/python3.5/concurrent/futures/_base.py", line 398, in result
2020-08-30 18:04:20 [INFO] return self.__get_result()
2020-08-30 18:04:20 [INFO] File "/usr/lib/python3.5/concurrent/futures/_base.py", line 357, in __get_result
2020-08-30 18:04:20 [INFO] raise self._exception
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/tenacity/__init__.py", line 412, in call
2020-08-30 18:04:20 [INFO] result = fn(*args, **kwargs)
2020-08-30 18:04:20 [INFO] File "/tmp/tmp.hGTgnOHgsK/func/lib/python3.5/site-packages/zaza/openstack/charm_tests/octavia/tests.py", line 247, in _get_payload
2020-08-30 18:04:20 [INFO] universal_newlines=True)
2020-08-30 18:04:20 [INFO] File "/usr/lib/python3.5/subprocess.py", line 626, in check_output
2020-08-30 18:04:20 [INFO] **kwargs).stdout
2020-08-30 18:04:20 [INFO] File "/usr/lib/python3.5/subprocess.py", line 708, in run
2020-08-30 18:04:20 [INFO] output=stdout, stderr=stderr)
2020-08-30 18:04:20 [INFO] subprocess.CalledProcessError: Command '['wget', '-O', '-', 'http://172.17.112.227/']' returned non-zero exit status 4
2020-08-30 18:04:20 [INFO] ----------------------------------------------------------------------
2020-08-30 18:04:20 [INFO] Ran 1 test in 2955.991s
2020-08-30 18:04:20 [INFO] FAILED
2020-08-30 18:04:20 [INFO] (errors=1)