Bump num-bigint from 0.4.1 to 0.4.2

Bumps [num-bigint](https://github.com/rust-num/num-bigint) from 0.4.1 to 0.4.2.
- [Release notes](https://github.com/rust-num/num-bigint/releases)
- [Changelog](https://github.com/rust-num/num-bigint/blob/master/RELEASES.md)
- [Commits](https://github.com/rust-num/num-bigint/compare/num-bigint-0.4.1...num-bigint-0.4.2)

---
updated-dependencies:
- dependency-name: num-bigint
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Cargo.lock

@@ -1144,9 +1144,9 @@ dependencies = [
 
 [[package]]
 name = "num-bigint"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "76e97c412795abf6c24ba30055a8f20642ea57ca12875220b854cfa501bf1e48"
+checksum = "74e768dff5fb39a41b3bcd30bb25cf989706c90d028d1ad71971987aa309d535"
 dependencies = [
  "autocfg",
  "num-integer",