chore(deps): bump syn from 1.0.80 to 1.0.81 (#535)

Bumps [syn](https://github.com/dtolnay/syn) from 1.0.80 to 1.0.81.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/1.0.80...1.0.81)

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Cargo.lock

@@ -2785,9 +2785,9 @@ checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
 
 [[package]]
 name = "syn"
-version = "1.0.80"
+version = "1.0.81"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d010a1623fbd906d51d650a9916aaefc05ffa0e4053ff7fe601167f3e715d194"
+checksum = "f2afee18b8beb5a596ecb4a2dce128c719b4ba399d34126b9e4396e3f9860966"
 dependencies = [
  "proc-macro2",
  "quote",

ethers-core/Cargo.toml

@@ -35,7 +35,7 @@ once_cell = "1.8.0"
 
 # eip712 feature enabled dependencies
 convert_case = { version = "0.4.0", optional = true }
-syn = { version = "1.0.80", optional = true }
+syn = { version = "1.0.81", optional = true }
 quote = { version = "1.0.9", optional = true }
 proc-macro2 = { version = "1.0.32", optional = true }