Port clang-format config to clang-format-18 and upgrade the github CI to ubuntu-22.04

Port clang-format config to clang-format-18 and upgrade the github CI to ubuntu-22.04

In PR #1022 I am downgrading the codegen step from ubuntu-latest (now 24-04 using clang-format-18 since a few weeks) to ubuntu-22.04 because our clang-format config uses clang-format-15 at the latest