Check port availability

[lyw07]

Summary

This PR is to fix the issue that the function for port availability check does not really work. Previously, because of the wrong host, the unavailable port error is not caught by the function check_port_availability but by cherrypy.

Reviewer guidance

1. Run ka-lite or some other program to occupy the port
2. Run kolibri with the same port and see the output on terminal

References

#4189

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Contributor Checklist

• Contributor has fully tested the PR manually
• PR has the correct target branch and milestone
• PR has 'needs review' or 'work-in-progress' label
• If PR is ready for review, a reviewer has been added. (Don't use 'Assignees')
• If there are any front-end changes, before/after screenshots are included
• If this is an important user-facing change, PR or related issue has a 'changelog' label

Reviewer Checklist

• Automated test coverage is satisfactory
• Reviewer has fully tested the PR manually
• PR has been tested for accessibility regressions
• External dependencies files were updated (yarn and pip)
• Documentation is updated
• Link to diff of internal dependency change is included
• CHANGELOG.rst is updated for high-level changes
• Contributor is in AUTHORS.rst

[codecov]

Codecov Report

Merging #4333 into develop will decrease coverage by <.01%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           develop    #4333      +/-   ##
===========================================
- Coverage    52.92%   52.91%   -0.01%     
===========================================
  Files          718      718              
  Lines        22813    22810       -3     
  Branches      3096     3096              
===========================================
- Hits         12073    12070       -3     
  Misses       10017    10017              
  Partials       723      723

Impacted Files	Coverage Δ
kolibri/utils/sanity_checks.py	100% <100%> (ø)	⬆️

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[mrpau-richard]

@lyw07 I tested this PR in Ubuntu, and it did display the port occupied errors in the terminal.

But on Windows it's still saying at the Command prompt that the kolibri running on occupied port.(refer to the screenshot below)

[lyw07]

@mrpau-richard thank you for testing! I just pushed the fix for Windows and tested the Windows installer. It should be working now :)

[mrpau-richard]

Great work @lyw07 , I tested it at the Windows. The port error logs are now working in the Command prompt.

[mrpau-richard]

I Tested this @lyw07.

[lyw07]

@mrpau-richard thank you so much for testing!

[benjaoming]

Great + simplifying changes. portend is already a dependency of cherrypy, so no problem depending on it... just keep in mind that we'll follow the inferred cherrypy version requirements for this one.

[indirectlylit]

made the timeout into a constant as requested