Update README with correct URL and Linux test instructions

[vitusortner]

No description provided.

[codecov]

Codecov Report

Merging #253 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #253   +/-   ##
========================================
  Coverage    81.17%   81.17%           
========================================
  Files           51       51           
  Lines         1376     1376           
========================================
  Hits          1117     1117           
  Misses         259      259

Flag	Coverage Δ
#floor	81.17% <ø> (ø)	⬆️
#floor_generator	80.48% <ø> (ø)	⬆️

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