Fix #932 : fix start scene button in scene list

[Pierre-Gilles]

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[codecov]

Codecov Report

Merging #936 (f2d481d) into master (15c063a) will increase coverage by 0.19%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #936      +/-   ##
==========================================
+ Coverage   94.02%   94.22%   +0.19%     
==========================================
  Files         462      462              
  Lines        6130     6133       +3     
==========================================
+ Hits         5764     5779      +15     
+ Misses        366      354      -12     

Impacted Files	Coverage Δ
server/api/websockets/index.js	56.66% <100.00%> (+23.33%)	⬆️

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