Update syn requirement from 1.0.109 to 2.0.58

Updates the requirements on [syn](https://github.com/dtolnay/syn) to permit the latest version.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@1.0.109...2.0.58)

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

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

tagged-base64-macros/Cargo.toml

@@ -14,5 +14,5 @@ default = ["serde"]
 serde = []
 
 [dependencies]
-syn = { version = "1.0.109", features = ["full", "extra-traits"] }
+syn = { version = "2.0.58", features = ["full", "extra-traits"] }
 quote = "1.0"