[master] Do not make Salt CLI to crash when there are IPv6 established connections

[meaksh]

This PR ports #52888 to master branch, and fixes an issue at 2019.2.x release.

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What does this PR do?

This PR fixes an issue in utils/network.py which is making the Salt CLI to crash when some of the targeted minions cannot be reached.

Currently, the _netlink_tool_remote_on function is not taking care of possible IPv6 entries returned by ss -ant.

When there are minions that did not response on time, then this code is executed. In case the underlying call to ss -ant returns an IPv6 entry, this would make the Salt CLI to crash while trying to parse the host/port.

Previous Behavior

# salt '*' test.ping
minion1:
    True
minion2:
    True
[ERROR   ] An un-handled exception was caught by salt's global exception handler:
ValueError: invalid literal for int() with base 10: ':ffff:10.111.111.111]:9100'
Traceback (most recent call last):
  File "/usr/bin/salt", line 10, in <module>
    salt_main()
  File "/usr/lib/python3.6/site-packages/salt/scripts.py", line 516, in salt_main
    client.run()
  File "/usr/lib/python3.6/site-packages/salt/cli/salt.py", line 194, in run
    for full_ret in cmd_func(**kwargs):
  File "/usr/lib/python3.6/site-packages/salt/client/__init__.py", line 746, in cmd_cli
    **kwargs):
  File "/usr/lib/python3.6/site-packages/salt/client/__init__.py", line 1508, in get_cli_event_returns
    connected_minions = salt.utils.minions.CkMinions(self.opts).connected_ids()
  File "/usr/lib/python3.6/site-packages/salt/utils/minions.py", line 643, in connected_ids
    addrs = salt.utils.network.local_port_tcp(int(self.opts['publish_port']))
  File "/usr/lib/python3.6/site-packages/salt/utils/network.py", line 1384, in local_port_tcp
    ret = _remotes_on(port, 'local_port')
  File "/usr/lib/python3.6/site-packages/salt/utils/network.py", line 1402, in _remotes_on
    ret = _netlink_tool_remote_on(port, which_end)
  File "/usr/lib/python3.6/site-packages/salt/utils/network.py", line 1494, in _netlink_tool_remote_on
    if which_end == 'local_port' and int(local_port) != port:
ValueError: invalid literal for int() with base 10: ':ffff:10.111.111.111]:9100'

New Behavior

# salt '*' test.ping
minion1:
    True
minion2:
    True
minion3:
    Minion did not return. [No response]
ERROR: Minions returned with non-zero exit code

Tests written?

Yes

Commits signed with GPG?

Yes

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[dwoz]

@meaksh Please address the test failures.

[meaksh]

@dwoz the test failure should be fixed now 👍

[dwoz]

@meaksh Awesome, thanks!