Update aws bedrock agent runtime gem

[cearachew]

Update to the AWS bedrock agent runtime gem to support new API features in the retrieve and generate call

• Guardrails support
• model invocation output traces
• orchestration configuration
• streaming api
• reranking support
• performance configuration

This doesn't update the aws-sdk-bedrockagentruntime gem all the way to 1.57, because of conflicts with aws-google for the required aws-sdk-core version. This should be resolved later, but the update to 1.38 is enough for now. Conflict output:

Bundler could not find compatible versions for gem "aws-sdk-core":
  In Gemfile:
    aws-sdk-core

    aws-google (~> 0.2.3) was resolved to 0.2.3, which depends on
      aws-sdk-core (~> 3.211.0)

    aws-sdk-bedrockagentruntime (~> 1.39.0) was resolved to 1.39.0, which depends on
      aws-sdk-core (>= 3.216.0, ~> 3)

Links

Jira: https://codedotorg.atlassian.net/browse/AITT-1049

Testing story

This shouldn't require code or test changes. Local build worked ok (the required API fields for retrieveandgenerate didn't change), waiting on drone for more tests

PR Checklist:

• Tests provide adequate coverage
• Privacy and Security impacts have been assessed
• Code is well-commented
• New features are translatable or updates will not break translations
• Relevant documentation has been added or updated
• User impact is well-understood and desirable
• Pull Request is labeled appropriately
• Follow-up work items (including potential tech debt) are tracked and linked

[cearachew]

@cat5inthecradle can you take a look at this gem update?