Update indexmap requirement from 1.6.1 to 2.0.2

Updates the requirements on [indexmap](https://github.com/bluss/indexmap) to permit the latest version.
- [Changelog](https://github.com/bluss/indexmap/blob/master/RELEASES.md)
- [Commits](indexmap-rs/indexmap@1.6.1...2.0.2)

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

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

algonaut_crypto/Cargo.toml

@@ -15,7 +15,7 @@ version = "0.4.2"
 algonaut_encoding = { path = "../algonaut_encoding", version = "0.4.2" }
 data-encoding = "2.3.1"
 derive_more = "0.99.13"
-indexmap = "1.6.1"
+indexmap = "2.0.2"
 lazy_static = "1.4.0"
 serde = { version = "1.0", features = ["derive"] }
 sha2 = "0.10.1"