Bump aws-sdk-core from 3.168.3 to 3.168.4

Bumps [aws-sdk-core](https://github.com/aws/aws-sdk-ruby) from 3.168.3 to 3.168.4.
- [Release notes](https://github.com/aws/aws-sdk-ruby/releases)
- [Changelog](https://github.com/aws/aws-sdk-ruby/blob/version-3/gems/aws-sdk-core/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-ruby/commits)

---
updated-dependencies:
- dependency-name: aws-sdk-core
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -291,8 +291,8 @@ GEM
     awesome_nested_set (3.5.0)
       activerecord (>= 4.0.0, < 7.1)
     aws-eventstream (1.2.0)
-    aws-partitions (1.673.0)
-    aws-sdk-core (3.168.3)
+    aws-partitions (1.674.0)
+    aws-sdk-core (3.168.4)
       aws-eventstream (~> 1, >= 1.0.2)
       aws-partitions (~> 1, >= 1.651.0)
       aws-sigv4 (~> 1.5)