Support latest libtorch 2.2.x

[pfxuan]

This PR is able to build both old and latest libtorch versions. It also fixes https://github.com/pierotofy/OpenSplat/issues/17. The root cause of the Compilation error is a bit complicated and seems having a long tail:

• Eliminate c10::guts::to_string
• [1/N] Elimates c10::to_string
• [Reland] Elimates c10::guts::to_string
• [1/N] Elimates c10::to_string and other STL string workarounds

The updated build matrix: os: [ubuntu-22.04, ubuntu-20.04] torch-version: [2.1.2, 2.2.1] cuda-version: ['cu118', 'cu121'] cmake-build-type: [Release]

[pierotofy]

Thanks for looking into this and for the PR @pfxuan ! This looks 👍