Update cargo_toml requirement from 0.19 to 0.20 in /services/autorust (#1646)

Updates the requirements on [cargo_toml](https://gitlab.com/lib.rs/cargo_toml) to permit the latest version.
- [Commits](https://gitlab.com/lib.rs/cargo_toml/compare/v0.19.0...v0.20.0)

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

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

Author: dependabot[bot]

services/autorust/codegen/Cargo.toml

@@ -26,7 +26,7 @@ camino = "1.1"
 askama = "0.12"
 toml = "0.8"
 qstring = "0.7"
-cargo_toml = "0.19"
+cargo_toml = "0.20"
 
 [dev-dependencies]
 thiserror = "1.0"