Rebuild for libboost 1.86

[regro-cf-autotick-bot]

This PR has been triggered in an effort to update libboost186.

Notes and instructions for merging this PR:

1. Please merge the PR only after the tests have passed.
2. Feel free to push to the bot's branch to update this PR if needed.

Please note that if you close this PR we presume that the feedstock has been rebuilt, so if you are going to perform the rebuild yourself don't close this PR until the your rebuild has been merged.

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_{This PR was created by the regro-cf-autotick-bot. The regro-cf-autotick-bot is a service to automatically track the dependency graph, migrate packages, and propose package version updates for conda-forge. Feel free to drop us a line if there are any issues! This PR was generated by https://github.com/regro/cf-scripts/actions/runs/10431372333 - please use this URL for debugging.}

[conda-forge-webservices[bot]]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe/meta.yaml) and found it was in an excellent condition.

[h-vetinari]

This runs afoul of some of the deprecated stuff that got removed in boost::filesystem:

/home/conda/feedstock_root/build_artifacts/fenics-pkgs_1723892379242/work/dolfin/io/File.cpp:150:52: error: 'extension' is not a member of 'boost::filesystem'
  150 |   const std::string extension = boost::filesystem::extension(path);
      |                                                    ^~~~~~~~~
/home/conda/feedstock_root/build_artifacts/fenics-pkgs_1723892379242/work/dolfin/io/File.cpp:157:26: error: 'extension' is not a member of 'boost::filesystem'
  157 |       boost::filesystem::extension(boost::filesystem::basename(path));
      |                          ^~~~~~~~~
/home/conda/feedstock_root/build_artifacts/fenics-pkgs_1723892379242/work/dolfin/io/File.cpp:157:55: error: 'basename' is not a member of 'boost::filesystem'; did you mean 'rename'?
  157 |       boost::filesystem::extension(boost::filesystem::basename(path));
      |                                                       ^~~~~~~~
      |                                                       rename

[minrk]

upstream is looking into a patch this week, looks pretty small, I think. fenics is mostly not under development in favor of fenicsx, but it still has users, so I have to weigh which updates are worth pursuing vs letting outdated software stick with outdated dependencies.

[regro-cf-autotick-bot]

I see that this PR has conflicts, and I'm the only committer. I'm going to close this PR and will make another one as appropriate. This was generated by https://github.com/regro/cf-scripts/actions/runs/10746494116 - please use this URL for debugging,