build: bump libfuzzer-sys from 0.4.2 to 0.4.3 in /fuzz

Bumps [libfuzzer-sys](https://github.com/rust-fuzz/libfuzzer) from 0.4.2 to 0.4.3.
- [Release notes](https://github.com/rust-fuzz/libfuzzer/releases)
- [Changelog](https://github.com/rust-fuzz/libfuzzer/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-fuzz/libfuzzer/compare/0.4.2...0.4.3)

---
updated-dependencies:
- dependency-name: libfuzzer-sys
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

fuzz/Cargo.toml

@@ -11,7 +11,7 @@ cargo-fuzz = true
 [dependencies]
 block_util = { path = "../block_util" }
 libc = "0.2.119"
-libfuzzer-sys = "0.4.2"
+libfuzzer-sys = "0.4.3"
 qcow = { path = "../qcow" }
 seccompiler = "0.2.0"
 vhdx = { path = "../vhdx" }