UI language negotiation fix

[namedgraph]

With these fixes applied we are not experiencing #1453 anymore.

Reasons for creating this PR

Code fix and configuration fix

Link to relevant issue(s), if any

• Closes Skosmos UI loads in Arabic #1453

Description of the changes in this PR

• Pass language value to in_array() as string instead of object
• Replaced _ with - in skosmos:languages language tags found in the dockerfiles configuration files

Known problems or uncertainties in this PR

Checklist

• phpUnit tests pass locally with my changes
• I have added tests that show that the new code works, or tests are not relevant for this PR (e.g. only HTML/CSS changes)
• The PR doesn't reduce accessibility of the front-end code (e.g. tab focus, scaling to different resolutions, use of .sr-only class, color contrast)
• The PR doesn't introduce unintended code changes (e.g. empty lines or useless reindentation)

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (a6f1795) 69.57% compared to head (0c5e300) 69.57%.

Additional details and impacted files

@@            Coverage Diff            @@
##             master    #1455   +/-   ##
=========================================
  Coverage     69.57%   69.57%           
  Complexity     1651     1651           
=========================================
  Files            32       32           
  Lines          4259     4259           
=========================================
  Hits           2963     2963           
  Misses         1296     1296           

Impacted Files	Coverage Δ
controller/WebController.php	15.59% <0.00%> (ø)

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[osma]

Thanks a lot @namedgraph , this looks like a very reasonable set of fixes.

The code that this PR is targeting is really begging for unit tests. I think this would be the right moment to add those tests, verifying that the fix actually worked. I will see if I can add those easily before merging. This needs to go both to the master branch and to the skosmos-3 branch where we have started to develop version 3 of Skosmos.

[osma]

I implemented unit tests for the guessLanguage method, then applied the commits from this PR on top, and put it into PR #1457 which supersedes this one.

[osma]

Merged via #1457. Thanks again!

[namedgraph]

You're welcome :)