Bump strum from 0.21.0 to 0.24.1

Bumps [strum](https://github.com/Peternator7/strum) from 0.21.0 to 0.24.1.
- [Release notes](https://github.com/Peternator7/strum/releases)
- [Changelog](https://github.com/Peternator7/strum/blob/master/CHANGELOG.md)
- [Commits](https://github.com/Peternator7/strum/commits)

---
updated-dependencies:
- dependency-name: strum
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

bridges/relays/bin-substrate/Cargo.toml

@@ -19,7 +19,7 @@ rbtag = "0.3"
 structopt = "0.3"
 signal-hook = "0.3.14"
 signal-hook-async-std = "0.2.2"
-strum = { version = "0.21.0", features = ["derive"] }
+strum = { version = "0.24.1", features = ["derive"] }
 
 # Bridge dependencies
 bp-header-chain = { path = "../../primitives/header-chain" }