Refactor device room selector

[atrovato]

Pull Request check-list

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• [ ] 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 you are adding a new features/services, did you run integration comparator? (npm run compare-translations on front)
• [ ] Did you test this pull request in real life? With real devices? If this development is a big feature or a new service, we recommend that you provide a Docker image to the community for testing before merging.
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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[bot]]

Codecov Report

Merging #23 (bcbb123) into master (7547381) will not change coverage. The diff coverage is n/a.

:exclamation: Current head bcbb123 differs from pull request most recent head 810c8b0. Consider uploading reports for the commit 810c8b0 to get more accurate results

@@           Coverage Diff           @@
##           master      #23   +/-   ##
=======================================
  Coverage   96.54%   96.54%           
=======================================
  Files         613      613           
  Lines        8729     8729           
=======================================
  Hits         8427     8427           
  Misses        302      302           

Impacted Files	Coverage Δ
server/utils/constants.js	100.00% <0.00%> (ø)

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