build(deps): bump syn from 1.0.55 to 1.0.56

Bumps [syn](https://github.com/dtolnay/syn) from 1.0.55 to 1.0.56.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/1.0.55...1.0.56)

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

Cargo.lock

@@ -1664,9 +1664,9 @@ checksum = "1e81da0851ada1f3e9d4312c704aa4f8806f0f9d69faaf8df2f3464b4a9437c2"
 
 [[package]]
 name = "syn"
-version = "1.0.55"
+version = "1.0.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a571a711dddd09019ccc628e1b17fe87c59b09d513c06c026877aa708334f37a"
+checksum = "a9802ddde94170d186eeee5005b798d9c159fa970403f1be19976d0cfb939b72"
 dependencies = [
  "proc-macro2",
  "quote",