Update hex requirement from 0.3 to 0.4

Updates the requirements on [hex](https://github.com/KokaKiwi/rust-hex) to permit the latest version.
- [Release notes](https://github.com/KokaKiwi/rust-hex/releases)
- [Commits](https://github.com/KokaKiwi/rust-hex/commits)

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

Author: dependabot-preview[bot]

Cargo.toml

@@ -35,7 +35,7 @@ fs2 = "0.4"
 git2 = "0.10.0"
 git2-curl = "0.11.0"
 glob = "0.3.0"
-hex = "0.3"
+hex = "0.4"
 home = "0.5"
 humantime = "1.2.0"
 ignore = "0.4.7"