Change Docker port to 80

[Pierre-Gilles]

Pull Request check-list

To ensure your Pull Request can be accepted as fast as possible, make sure to review and check all of these items:

• If your changes affects code, did your write the tests?
• Are tests passing? (npm test on both front/server)
• Is the linter passing? (npm run eslint on both front/server)
• Did you run prettier? (npm run prettier on both front/server)
• If your changes modify the API (REST or Node.js), did you modify the documentation? (Documentation is based on comments in code)

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Description of change

Please provide a description of the change here. It's always best with screenshots, so don't hesitate to add some!

[codecov]

Codecov Report

Merging #523 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #523   +/-   ##
=======================================
  Coverage   91.14%   91.14%           
=======================================
  Files         334      334           
  Lines        3794     3794           
=======================================
  Hits         3458     3458           
  Misses        336      336

Flag	Coverage Δ
#server	91.14% <ø> (ø)	⬆️

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