Bump fast-xml-parser and @aws-sdk/client-s3 in /backend

Bumps [fast-xml-parser](https://github.com/NaturalIntelligence/fast-xml-parser) and [@aws-sdk/client-s3](https://github.com/aws/aws-sdk-js-v3/tree/HEAD/clients/client-s3). These dependencies needed to be updated together.

Updates `fast-xml-parser` from 4.2.5 to 4.4.1
- [Release notes](https://github.com/NaturalIntelligence/fast-xml-parser/releases)
- [Changelog](https://github.com/NaturalIntelligence/fast-xml-parser/blob/master/CHANGELOG.md)
- [Commits](NaturalIntelligence/fast-xml-parser@v4.2.5...v4.4.1)

Updates `@aws-sdk/client-s3` from 3.499.0 to 3.637.0
- [Release notes](https://github.com/aws/aws-sdk-js-v3/releases)
- [Changelog](https://github.com/aws/aws-sdk-js-v3/blob/main/clients/client-s3/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-js-v3/commits/v3.637.0/clients/client-s3)

---
updated-dependencies:
- dependency-name: fast-xml-parser
  dependency-type: indirect
- dependency-name: "@aws-sdk/client-s3"
  dependency-type: indirect
...

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