Bump regex-syntax from 0.6.6 to 0.6.8

Bumps [regex-syntax](https://github.com/rust-lang/regex) from 0.6.6 to 0.6.8.
- [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)

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

Cargo.lock

@@ -1010,14 +1010,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "aho-corasick 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex-syntax 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.6"
+version = "0.6.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "ucd-util 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1806,7 +1806,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum redox_syscall 0.1.54 (registry+https://github.com/rust-lang/crates.io-index)" = "12229c14a0f65c4f1cb046a3b52047cdd9da1f4b30f8a39c5063c8bae515e252"
 "checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
 "checksum regex 1.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "d9d8297cc20bbb6184f8b45ff61c8ee6a9ac56c156cec8e38c3e5084773c44ad"
-"checksum regex-syntax 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)" = "dcfd8681eebe297b81d98498869d4aae052137651ad7b96822f09ceb690d0a96"
+"checksum regex-syntax 0.6.8 (registry+https://github.com/rust-lang/crates.io-index)" = "9b01330cce219c1c6b2e209e5ed64ccd587ae5c67bed91c0b49eecf02ae40e21"
 "checksum remove_dir_all 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3488ba1b9a2084d38645c4c08276a1752dcbf2c7130d74f1569681ad5d2799c5"
 "checksum reqwest 0.9.18 (registry+https://github.com/rust-lang/crates.io-index)" = "00eb63f212df0e358b427f0f40aa13aaea010b470be642ad422bcbca2feff2e4"
 "checksum ring 0.13.5 (registry+https://github.com/rust-lang/crates.io-index)" = "2c4db68a2e35f3497146b7e4563df7d4773a2433230c5e4b448328e31740458a"