Adding supported regions for Bedrock Knowledge Base

[sleepwithcoffee]

https://docs.aws.amazon.com/bedrock/latest/userguide/knowledge-base-supported.html

As of today, Amazon Bedrock Knowledge Base has expanded its supported regions, the solution should allow passing in the region in the config cli:

• US East (N. Virginia)
• US East (Ohio)
• US West (Oregon)
• AWS GovCloud (US-East)
• AWS GovCloud (US-West)
• Asia Pacific (Tokyo)
• Asia Pacific (Seoul)
• Asia Pacific (Mumbai)
• Asia Pacific (Singapore)
• Asia Pacific (Sydney)
• Canada (Central)
• Europe (Frankfurt)
• Europe (Zurich)
• Europe (Stockholm)
• Europe (Ireland)
• Europe (London)
• Europe (Paris)
• South America (São Paulo)