I had to apply these changes for OSS-Fuzz to continue working.
Specifically I needed to add `cargo-features = ['named-profiles']` and
`inherits` for any profile other than `release`. However, I have also
confirmed now that the building is done with optimized + debuginfo
in OSS-Fuzz (`Finished release [optimized + debuginfo] target(s) in
37.59s`).
The problem was that the fuzzer wasn't running with optimizations, which
means it was likely compiled in debug mode. So setting the optimization
level on the release profile won't do any good. Instead, we set it on
the debug and test profiles, which should cover it.
