[CI/CD] Not all CI steps use the same warning levels when compiling

[cecille]

Looks like at least some of our CI / builders let through unused variables. We should turn this on everywhere. see https://github.com/project-chip/connectedhomeip/pull/30793/commits/d3752baacd322a78bcffae4d78fc2b0c64afe72f

Also...some let through code with missing semicolons somehow. I don't even know how that can happen, but see https://github.com/project-chip/connectedhomeip/pull/30793/commits/a14846a9aa48f5f8f8c06603a3ebd97e9c67b636

[andy31415]

Missing semicolons sounds like the code may not have been compiled at all.

For the rest, unused variables is often a clang-tidy thing (along with many others, like no else after return) and those we run based on a compile_commands.json db which we build for tests only. It is also very slow to run.