Bump serde from 1.0.80 to 1.0.81

Bumps [serde](https://github.com/serde-rs/serde) from 1.0.80 to 1.0.81.
- [Release notes](https://github.com/serde-rs/serde/releases)
- [Commits](https://github.com/serde-rs/serde/compare/v1.0.80...v1.0.81)

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

sdk/Cargo.toml

@@ -15,7 +15,7 @@ generic-array = { version = "0.12.0", default-features = false, features = ["ser
 log = "0.4.2"
 ring = "0.13.2"
 sha2 = "0.8.0"
-serde = "1.0.27"
+serde = "1.0.81"
 serde_derive = "1.0.81"
 serde_json = "1.0.10"
 untrusted = "0.6.2"