build(deps): update bitflags requirement from 1.2.1 to 2.4.0

Updates the requirements on [bitflags](https://github.com/bitflags/bitflags) to permit the latest version.
- [Release notes](https://github.com/bitflags/bitflags/releases)
- [Changelog](https://github.com/bitflags/bitflags/blob/main/CHANGELOG.md)
- [Commits](bitflags/bitflags@1.2.1...2.4.0)

---
updated-dependencies:
- dependency-name: bitflags
  dependency-type: direct:production
...

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

Cargo.toml

@@ -27,7 +27,7 @@ required-features = ["ardupilotmega"]
 crc-any = { version = "2.3.5", default-features = false }
 num-traits = { version = "0.2", default-features = false }
 num-derive = "0.3.2"
-bitflags = "1.2.1"
+bitflags = "2.4.0"
 serial = { version = "0.4", optional = true }
 serde = { version = "1.0.115", optional = true, features = ["derive"] }
 byteorder = { version = "1.3.4", default-features = false }