build(deps): bump async and postman-code-generators

Bumps [async](https://github.com/caolan/async) to 3.2.4 and updates ancestor dependency [postman-code-generators](https://github.com/postmanlabs/code-generators). These dependencies need to be updated together.


Updates `async` from 2.6.3 to 3.2.4
- [Release notes](https://github.com/caolan/async/releases)
- [Changelog](https://github.com/caolan/async/blob/master/CHANGELOG.md)
- [Commits](caolan/async@v2.6.3...v3.2.4)

Updates `postman-code-generators` from 1.2.2 to 1.9.0
- [Release notes](https://github.com/postmanlabs/code-generators/releases)
- [Changelog](https://github.com/postmanlabs/postman-code-generators/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/postmanlabs/code-generators/commits/v1.9.0)

---
updated-dependencies:
- dependency-name: async
  dependency-type: indirect
- dependency-name: postman-code-generators
  dependency-type: direct:development
...

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