build(deps): update thiserror requirement from 1.0 to 2.0

Updates the requirements on [thiserror](https://github.com/dtolnay/thiserror) to permit the latest version.
- [Release notes](https://github.com/dtolnay/thiserror/releases)
- [Commits](dtolnay/thiserror@1.0.0...2.0.3)

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

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

cdevents-sdk/Cargo.toml

@@ -17,7 +17,7 @@ proptest = { version = "1.4", optional = true }
 proptest-derive = { version = "0.5", optional = true }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-thiserror = "1.0"
+thiserror = "2.0"
 time = { version = "0.3", features = ["serde-human-readable"] }
 
 [dev-dependencies]