Update benchmarking CI for cargo-codspeed v4 (#20686)
Summary
--
A new codspeed
[release](https://github.com/CodSpeedHQ/codspeed-rust/releases/tag/v4.0.0)
came out, and our CI was failing. It looks like the
previously-positional list of benchmarks now corresponds to a `--bench`
[flag](https://github.com/CodSpeedHQ/codspeed-rust/blob/7159cf86b9432243565e488c827c1663b5385fde/crates/cargo-codspeed/src/app.rs#L39-L43).
Test Plan
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CI on this PR
## TODO
- [x] Drop whitespace change commit, just wanted to make sure the
benchmarks ran
