Fix build with boost 1.85.0

[scpeters]

🦟 Bug fix

Fixes #3385.

Summary

The branch_path API was deprecated and has been removed in boost 1.85.0. This uses the recommended replacement method parent_path.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[scpeters]

this isn't quite enough; it's still failing

[scpeters]

looks like basename and extension were deprecated / removed as well

/Users/scpeters/ws/gazebo/src/gazebo/gazebo/util/LogPlay.cc:417:29: error: no member named 'basename' in namespace 'boost::filesystem'
  return boost::filesystem::basename(this->dataPtr->filename) +
         ~~~~~~~~~~~~~~~~~~~^
/Users/scpeters/ws/gazebo/src/gazebo/gazebo/util/LogPlay.cc:418:24: error: no member named 'extension' in namespace 'boost::filesystem'
    boost::filesystem::extension(this->dataPtr->filename);
    ~~~~~~~~~~~~~~~~~~~^
2 errors generated.

https://github.com/boostorg/filesystem/blob/boost-1.84.0/include/boost/filesystem/convenience.hpp#L28-L38

[scpeters]

looks like basename and extension were deprecated / removed as well

/Users/scpeters/ws/gazebo/src/gazebo/gazebo/util/LogPlay.cc:417:29: error: no member named 'basename' in namespace 'boost::filesystem'
  return boost::filesystem::basename(this->dataPtr->filename) +
         ~~~~~~~~~~~~~~~~~~~^
/Users/scpeters/ws/gazebo/src/gazebo/gazebo/util/LogPlay.cc:418:24: error: no member named 'extension' in namespace 'boost::filesystem'
    boost::filesystem::extension(this->dataPtr->filename);
    ~~~~~~~~~~~~~~~~~~~^
2 errors generated.

https://github.com/boostorg/filesystem/blob/boost-1.84.0/include/boost/filesystem/convenience.hpp#L28-L38

fix in 27c2277