[🔌 Provider]: AWS Opensearch with Serverless

[AlinVina]

Describe the provider you want to add
AWS Opensearch provider and Opensearch Serverless provider. Opensearch Serverless can use IAM roles to authenticate.
https://docs.aws.amazon.com/opensearch-service/latest/developerguide/security-iam-serverless.html
We are already using cloudwatch provider with an IAM role attached to the keep service accounts which provides the needed access. We would like to have the same possibility with this Opensearch provider.

Describe your use case
This will help us integrate Opensearch AWS into our keep which will help us correlate more alerts and logs.

Are you already using Keep?
Yes

Additional context
If we could us this provider the same way we use cloudwatch provider with an IAM role that would be great

[35C4n0r]

@shahargl can I get assigned !

[shahargl]

@35C4n0r assigned