chore(deps): update j4rs requirement from 0.19.0 to 0.20.0

Updates the requirements on [j4rs](https://github.com/astonbitecode/j4rs) to permit the latest version.
- [Commits](astonbitecode/j4rs@v0.19.0...v0.20.0)

---
updated-dependencies:
- dependency-name: j4rs
  dependency-type: direct:production
...

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

Cargo.toml

@@ -44,7 +44,7 @@ assert_matches = "1.5"
 criterion = { version = "0.5", features = ["async_tokio"] }
 dotenvy = "0.15.1"
 futures = "0.3"
-j4rs = "0.19.0"
+j4rs = "0.20.0"
 once_cell = "1.9"
 procspawn = "1.0"
 proptest = "1"