Format utils code

[jslee02]

dart-utils was not included in #1360, which was an oversight.

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Before creating a pull request

• Document new methods and classes
• Format new code files using clang-format

Before merging a pull request

• Set version target by selecting a milestone on the right side
• Summarize this change in CHANGELOG.md
• Add unit test(s) for this change

[codecov]

Codecov Report

Merging #1384 into master will increase coverage by 0.04%.
The diff coverage is 53.27%.

@@            Coverage Diff             @@
##           master    #1384      +/-   ##
==========================================
+ Coverage   56.95%   56.99%   +0.04%     
==========================================
  Files         366      366              
  Lines       27460    27415      -45     
==========================================
- Hits        15640    15626      -14     
+ Misses      11820    11789      -31

Impacted Files	Coverage Δ
dart/utils/CompositeResourceRetriever.hpp	100% <ø> (ø)	⬆️
dart/utils/urdf/urdf_world_parser.hpp	100% <ø> (ø)	⬆️
dart/utils/PackageResourceRetriever.hpp	100% <ø> (ø)	⬆️
dart/utils/FileInfoC3D.cpp	0% <0%> (ø)	⬆️
dart/utils/FileInfoDof.cpp	0% <0%> (ø)	⬆️
dart/utils/C3D.cpp	0% <0%> (ø)	⬆️
dart/utils/FileInfoC3D.hpp	0% <0%> (ø)	⬆️
dart/utils/VskParser.hpp	100% <100%> (ø)	⬆️
dart/utils/urdf/DartLoader.hpp	100% <100%> (ø)	⬆️
dart/utils/DartResourceRetriever.hpp	100% <100%> (ø)	⬆️
... and 12 more