Set policy CMP0167 to avoid warnings with CMake 3.30

[jorisv]

CMake 3.30 don't package anymore the FindBoost.cmake file. Instead, it encourage to use the BoostModule.cmake distributed by Boost.

To avoid a warning message, we must set the CMP0167 policy to NEW.

Here the policy documentation:

The FindBoost module is removed.

CMake 3.29 and below provide a FindBoost module, but it needs constant
updates to keep up with upstream Boost releases. Upstream Boost 1.70

and above provide a BoostConfig.cmake package configuration file.
find_package(Boost CONFIG) finds the upstream package directly,
without the find module.

CMake 3.30 and above prefer to not provide the FindBoost module
so that find_package(Boost) calls, without the CONFIG or
NO_MODULE options, find the upstream BoostConfig.cmake directly.
This policy provides compatibility for projects that have not been ported
to use the upstream Boost package.

The OLD behavior of this policy is for find_package(Boost) to
load CMake's FindBoost module. The NEW behavior is for
find_package(Boost) to search for the upstream BoostConfig.cmake.

This policy was introduced in CMake version 3.30.
It may be set by cmake_policy() or cmake_minimum_required().
If it is not set, CMake warns, and uses OLD behavior.

[github-actions]

👋 Hi,
This is a reminder message to please assign a proper label to this Pull Request.
The possible labels are:

• build_collision (build pinocchio with coal support)
• build_casadi (build pinoochio with casadi support)
• build_autodiff (build pinocchio with cppad support)
• build_codegen (build pinocchio with cppadcg support)
• build_extra (build pinocchio with extra algorithms)
• build_mpfr (build pinocchio with Boost.Multiprecision support)
• build_sdf (build pinocchio with sdf parser)
• build_accelerate
• build_all (build pinocchio with all the options stated above)

Thanks.