Gracefully handle failure of ifcfg due to multiple IP bindings.

[jamalex]

Summary

When an interface has multiple IPs bound to it, the following issue surfaces: ftao/python-ifcfg#34

This prevents Kolibri from starting at all.

After this PR, this situation is handled somewhat gracefully:

INFO     Running Kolibri with the following settings: kolibri.deployment.default.settings.base
INFO     Sqlite database Vacuum finished.
INFO     Running 'kolibri start' as daemon (system service)
ERROR    Error retrieving network interface list!
ERROR    Could not detect an IP address that Kolibri binds to, but try opening up the following addresses:

        http://localhost:8080
        http://127.0.0.1:8080

INFO     Going to daemon mode, logging to /home/user/.kolibri/logs/kolibri.txt

Reviewer guidance

Wasn't able to force a replication locally, but tested the fix on the remote server where the issue was being observed, and it worked.

References

Sidesteps issue caused by ftao/python-ifcfg#34

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Contributor Checklist

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Reviewer Checklist

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[codecov]

Codecov Report

Merging #5914 into release-v0.12.x will decrease coverage by <.01%.
The diff coverage is 66.66%.

Impacted Files	Coverage Δ
kolibri/utils/server.py	46.54% <66.66%> (-0.15%)	⬇️

[benjaoming]

Agreeing on the work-around! The upstream issue should be addressed, too, of course, but it's slightly complicated.