Bump fixedbitset from 0.4.2 to 0.5.1

Bumps [fixedbitset](https://github.com/petgraph/fixedbitset) from 0.4.2 to 0.5.1.
- [Release notes](https://github.com/petgraph/fixedbitset/releases)
- [Commits](https://github.com/petgraph/fixedbitset/commits/0.5.1)

---
updated-dependencies:
- dependency-name: fixedbitset
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

crates/libcgroups/Cargo.toml

@@ -23,7 +23,7 @@ cgroupsv2_devices = ["rbpf", "libbpf-sys", "errno", "libc", "nix/dir"]
 nix = { version = "0.27.1", features = ["signal", "user", "fs"] }
 procfs = "0.16.0"
 oci-spec = { version = "~0.6.4", features = ["runtime"] }
-fixedbitset = "0.4.2"
+fixedbitset = "0.5.1"
 serde = { version = "1.0", features = ["derive"] }
 rbpf = { version = "0.2.0", optional = true }
 libbpf-sys = { version = "1.3.0", optional = true }