chore(deps): update syn requirement from 1 to 2

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@1.0.0...2.0.38)

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

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

bottlerocket-template-helper/Cargo.toml

@@ -17,7 +17,7 @@ darling = "0.20"
 proc-macro2 = "1"
 quote = "1"
 serde_json = "1"
-syn = { version = "1", default-features = false, features = ["full", "parsing", "printing", "proc-macro", "visit-mut"] }
+syn = { version = "2", default-features = false, features = ["full", "parsing", "printing", "proc-macro", "visit-mut"] }
 
 
 [dev-dependencies]