chore: bump xml2js and aws-sdk in /stream_mem_stress_test

Bumps [xml2js](https://github.com/Leonidas-from-XIV/node-xml2js) and [aws-sdk](https://github.com/aws/aws-sdk-js). These dependencies needed to be updated together.

Updates `xml2js` from 0.4.19 to 0.5.0
- [Release notes](https://github.com/Leonidas-from-XIV/node-xml2js/releases)
- [Commits](Leonidas-from-XIV/node-xml2js@0.4.19...0.5.0)

Updates `aws-sdk` from 2.1148.0 to 2.1354.0
- [Release notes](https://github.com/aws/aws-sdk-js/releases)
- [Changelog](https://github.com/aws/aws-sdk-js/blob/master/CHANGELOG.md)
- [Commits](aws/aws-sdk-js@v2.1148.0...v2.1354.0)

---
updated-dependencies:
- dependency-name: xml2js
  dependency-type: indirect
- dependency-name: aws-sdk
  dependency-type: indirect
...

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

Author: dependabot[bot]