build: bump arbitrary from 1.1.4 to 1.1.6 in /fuzz

Bumps [arbitrary](https://github.com/rust-fuzz/arbitrary) from 1.1.4 to 1.1.6.
- [Release notes](https://github.com/rust-fuzz/arbitrary/releases)
- [Changelog](https://github.com/rust-fuzz/arbitrary/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-fuzz/arbitrary/compare/v1.1.4...v1.1.6)

---
updated-dependencies:
- dependency-name: arbitrary
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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

fuzz/Cargo.lock

@@ -24,9 +24,9 @@ dependencies = [
 
 [[package]]
 name = "arbitrary"
-version = "1.1.4"
+version = "1.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8931eb436ab9bf1980c6cb2b9d1ba5390cd6793b2c6e2d2ea8147da3570c2a2e"
+checksum = "f44124848854b941eafdb34f05b3bcf59472f643c7e151eba7c2b69daa469ed5"
 
 [[package]]
 name = "arc-swap"