chore: Bump @aws-sdk/client-ecs from 3.837.0 to 3.840.0

Bumps [@aws-sdk/client-ecs](https://github.com/aws/aws-sdk-js-v3/tree/HEAD/clients/client-ecs) from 3.837.0 to 3.840.0.
- [Release notes](https://github.com/aws/aws-sdk-js-v3/releases)
- [Changelog](https://github.com/aws/aws-sdk-js-v3/blob/main/clients/client-ecs/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-js-v3/commits/v3.840.0/clients/client-ecs)

---
updated-dependencies:
- dependency-name: "@aws-sdk/client-ecs"
  dependency-version: 3.840.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]