Bump ex_aws from 2.5.1 to 2.5.3 (#277)

Bumps [ex_aws](https://github.com/ex-aws/ex_aws) from 2.5.1 to 2.5.3.
- [Release notes](https://github.com/ex-aws/ex_aws/releases)
- [Changelog](https://github.com/ex-aws/ex_aws/blob/main/CHANGELOG.md)
- [Commits](https://github.com/ex-aws/ex_aws/commits)

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

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