Update regex-syntax requirement from ~0.7.5 to ~0.8.5

Updates the requirements on [regex-syntax](https://github.com/rust-lang/regex) to permit the latest version.
- [Release notes](https://github.com/rust-lang/regex/releases)
- [Changelog](https://github.com/rust-lang/regex/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/regex/commits)

---
updated-dependencies:
- dependency-name: regex-syntax
  dependency-type: direct:production
...

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

aws-lc-rs/Cargo.toml

@@ -67,7 +67,7 @@ regex = "~1.9.6"
 # Pinned dependency to preserve MSRV: ??? <= rust-version < 1.65.0
 regex-automata = "~0.3.9"
 # Pinned dependency to preserve MSRV: 1.60.0  <= rust-version < 1.65.0
-regex-syntax = "~0.7.5"
+regex-syntax = "~0.8.5"
 # Pinned to avoid build failure in older versions
 proc-macro2 = "1.0.60"
 # Pinned dependency to preserve MSRV: 1.63.0 <= rust-version < 1.67.0