ubuntu 22.04 (jammy) goes end-of-life before the tentacle release will, so the U release can finally drop support. we could do that on main as soon as we have full support for ubuntu 24.04 (noble) that support for jammy has left our package builds pinned to gcc-12, but noble goes up to gcc-14. according to https://en.cppreference.com/w/cpp/compiler_support.html#cpp23, that's likely good enough to make the switch to c++23 has anyone experimented with c++23 in ceph? our previous upgrades to c++17 and 20 took a considerable effort, so now is probably a good time to start planning for this. we won't be able to switch over until we've dropped jammy everywhere on main (jenkins checks, shaman builds), but we can start merging fixes in the meantime. there will surely be some compiler warnings to address