Security Lake Integration should support cross-account

[kclinden]

Is your feature request related to a problem? Please describe.
The 4.9.0 security lake integration currently assumes that the lambda function is running from the same account as AWS Security Lake. This should be ran from a different account the Lambda role should assume the Security Lake created role with an external id.

Describe the solution you'd like
Enhance the Security Lake integration to support cross account

Describe alternatives you've considered
Run the lambda in the same account as security lake which is not recommended by the AWS Security Reference Architecture

Additional context
Source - https://github.com/wazuh/wazuh-indexer/blob/4.9.0/integrations/amazon-security-lake/src/lambda_function.py#L50