Cmake: Remove custom Find<Package>.cmake modules

[LecrisUT]

Spglib and Eigen3 both provide native <Package>Config.cmake files. These should be used instead, particularly because the names do not match and the manual finds do not include dependencies, defines and other options shipped by <Package>Config.cmake.

Alternatively I also recommend for required packages to change find_package with FetchContent(FIND_PACKAGE_ARGS), and if some backwards compatibility is required, design the Find<Package>.cmake as follows: https://gitlab.com/octopus-code/octopus/-/blob/main/cmake/FindMETIS.cmake?ref_type=heads, where it tries in order: find_package(CONFIG) -> pkg-config -> manual import

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[ghutchis]

In principal, this is great, but it's not passing CI builds, e.g. on Ubuntu:

2024-01-26T00:05:01.9175988Z CMake Error at avogadro/core/CMakeLists.txt:111 (find_package):
2024-01-26T00:05:01.9177070Z   By not providing "FindSpglib.cmake" in CMAKE_MODULE_PATH this project has
2024-01-26T00:05:01.9178287Z   asked CMake to find a package configuration file provided by "Spglib", but
2024-01-26T00:05:01.9179179Z   CMake did not find one.
2024-01-26T00:05:01.9179520Z 
2024-01-26T00:05:01.9179823Z   Could not find a package configuration file provided by "Spglib" with any
2024-01-26T00:05:01.9180331Z   of the following names:
2024-01-26T00:05:01.9180524Z 
2024-01-26T00:05:01.9180631Z     SpglibConfig.cmake
2024-01-26T00:05:01.9180974Z     spglib-config.cmake
2024-01-26T00:05:01.9181154Z 
2024-01-26T00:05:01.9181407Z   Add the installation prefix of "Spglib" to CMAKE_PREFIX_PATH or set
2024-01-26T00:05:01.9182034Z   "Spglib_DIR" to a directory containing one of the above files.  If "Spglib"
2024-01-26T00:05:01.9182653Z   provides a separate development package or SDK, be sure it has been
2024-01-26T00:05:01.9183102Z   installed.
2024-01-26T00:05:01.9183241Z 
2024-01-26T00:05:01.9183246Z 

[LecrisUT]

The issue is that the openchemistry libraries are using spglib <2.10 where the proper packaging is introduced. These patches are already introduced in Fedora to properly support upstream packaging, and the tests there pass: https://copr.fedorainfracloud.org/coprs/lecris/dependencies/build/6950789/

[github-actions]

Here are the build results
Avogadro2.AppImage
macOS.dmg
Artifacts will only be retained for 90 days.

[ghutchis]

Okay, I've updated openchemistry to spglib 2.10 so I'll re-run the builds.

[github-actions]

Here are the build results
Avogadro2.AppImage
macOS.dmg
Artifacts will only be retained for 90 days.

[github-actions]

Here are the build results
Avogadro2.AppImage
macOS.dmg
Win64.exe
Artifacts will only be retained for 90 days.

[ghutchis]

Great - looks like the work you did on more recent spglib solved the Windows build issue.

Thanks!

[welcome]

Congrats on merging your first pull request! 🎉 Thanks for making Avogadro better for everyone!

[github-actions]

Here are the build results
Avogadro2.AppImage
macOS.dmg
Win64.exe
Artifacts will only be retained for 90 days.