Remove warning of ImGuiViewer + OSG shadow

[jslee02]

The incompatibility issue of ImGuiViewer + OSG shadow found in #978 was fixed in #1274. Particularly, these two blocks (1, 2) resolved the issue.

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• Document new methods and classes
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• Set version target by selecting a milestone on the right side
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[codecov]

Codecov Report

Merging #1312 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1312      +/-   ##
==========================================
+ Coverage   57.18%   57.19%   +0.01%     
==========================================
  Files         366      366              
  Lines       27023    27023              
==========================================
+ Hits        15452    15457       +5     
+ Misses      11571    11566       -5

Impacted Files	Coverage Δ
dart/dynamics/EulerJoint.cpp	70.73% <0%> (+3.04%)	⬆️