Update jsonwebtoken requirement from 8 to 9 in /spiffe

Updates the requirements on [jsonwebtoken](https://github.com/Keats/jsonwebtoken) to permit the latest version.
- [Changelog](https://github.com/Keats/jsonwebtoken/blob/master/CHANGELOG.md)
- [Commits](Keats/jsonwebtoken@v8.0.0...v9.3.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

spiffe/Cargo.toml

@@ -21,7 +21,7 @@ url = "2"
 asn1 = { package = "simple_asn1", version = "0.6" }
 x509-parser = "0.16"
 pkcs8 = "0.10"
-jsonwebtoken = "8"
+jsonwebtoken = "9"
 jsonwebkey = { version = "0.3", features = ["jsonwebtoken", "jwt-convert"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"