[AWS Security Hub] - Create a new integration to support OCSF format findings

[brijesh-elastic]

Create a new integration to support findings in OCSF v1.5 (2002, 2003, 2004, 2006) format for AWS Security Hub. Follow the document for OCSF to ECS mappings.

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)