ref. https://github.com/jrl-umi3218/jrl-cmakemodules/issues/338
and fix deprecation warning about CMake 3.5 from CMake 3.27

* [cmake] Supporting pinocchio installed with cppad

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci



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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

- Avoid CMAKE_PACKAGE_REGISTRY
- Use Eigen3::Eigen if available

cross_implementation was missing

ref https://github.com/loco-3d/multicontact-api/issues/5

ref. https://github.com/stack-of-tasks/eigenpy/issues/126
cc. @stonneau

While here, add it to the .pc