Check (all?) backends of profiling in CI

[ErichDonGubler]

WGPU has had a multitude of compilation failures that make it into mainline history, caused by subtle differences in profiling backends. Some examples:

• wgpu-core compile failure with profile-with-tracing profiling feature #1477
• [v0.12] Fix profiling compile error under tracy and tracing #2332
• Fix trac(y/ing) compile issue #2333
• cargo clippy fails on call into profiling #5991
• Fix profiling with tracy. #5988
• Fix missing binding in wgpu-core/src/instance.rs when profiling has a backend enabled #6422

The root cause is, according to aclysma/profiling#87 (comment), significant tension between profiling wanting to be portable but also zero-cost when no backends are enabled, and no guarantee from Rust that unused expressions' side effects will be discarded. Resolving the root cause is interesting, but does not appear simple.

In the meantime, we can “simply” check profiling backends in CI, to ensure that we don't merge PRs that cause this again. If we can do this, we can mitigate the risk of the above problem, without actually needing to resolve it.