Bump syn from 2.0.11 to 2.0.12

Bumps [syn](https://github.com/dtolnay/syn) from 2.0.11 to 2.0.12.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@2.0.11...2.0.12)

---
updated-dependencies:
- dependency-name: syn
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Cargo.lock

@@ -9,7 +9,7 @@ description = "Proc macros provided by the parachain-system pallet"
 proc-macro = true
 
 [dependencies]
-syn = "2.0.11"
+syn = "2.0.12"
 proc-macro2 = "1.0.52"
 quote = "1.0.26"
 proc-macro-crate = "1.3.1"