Bump rusoto_core from 0.43.0 to 0.48.0

Bumps [rusoto_core](https://github.com/rusoto/rusoto) from 0.43.0 to 0.48.0.
- [Release notes](https://github.com/rusoto/rusoto/releases)
- [Changelog](https://github.com/rusoto/rusoto/blob/master/CHANGELOG.md)
- [Commits](rusoto/rusoto@mock-v0.43.0...mock-v0.48.0)

---
updated-dependencies:
- dependency-name: rusoto_core
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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