Handle no enabled ipv4 addresses in the network integration

[bdraco]

Proposed change

Fixes

2022-01-03 13:46:08 ERROR (MainThread) [homeassistant.setup] Error during setup of component http
Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.9/site-packages/homeassistant/setup.py", line 229, in _async_setup_component
    result = await task
  File "/srv/homeassistant/lib/python3.9/site-packages/homeassistant/components/http/__init__.py", line 192, in async_setup
    local_ip = await async_get_source_ip(hass)
  File "/srv/homeassistant/lib/python3.9/site-packages/homeassistant/components/network/__init__.py", line 35, in async_get_source_ip
    return source_ip if source_ip in all_ipv4s else all_ipv4s[0]
IndexError: list index out of range

Reported here: https://community.home-assistant.io/t/2021-12-new-configuration-menu-the-button-entity-and-gorgeous-area-cards/365680/776?u=bdraco

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

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