cross-region-support-cache level changes

[shiva958]

Issue #, if available:
Currently, the design for the caching layer only accepts a single instance of S3ControlClient during initializations. The problem with this is that, the S3ControlClient is configured for one region and cannot be used for making cross-region requests. Since, S3ControlClients do not have a cross-region setting to redirect requests to the correct region, we will be making headbucket requests to determine the correct region for the bucket and configure the S3ControlClient accordingly.

Description of changes:

• modifying the cache layers to remove passing S3ControlClients as part of the builder. Control Clients configured to the correct region will instead be passed as an input for the method that will be invoked by the plugin.
• Adding a Bucket Region cache. This region fetched for the bucket will be cached to avoid throttling S3 head bucket API.
• Adding and modifying unit tests.

Testing:
This PR is part of a large subset of PR's. Changes have been tested by running

• Unit-tests
• Integration-tests
• Spinning multiple threads in parallel sharing a single instance of s3client to send requests supported by Access Grants.

Coverage:
Cache layer - 86%

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[amitvc]

Minor comments. Approved

[amitvc]

Nit: Make this interface BucketRegionResolver and the impl S3AccessGrantsBucketRegionResolver.
Make interface names very generic and not specific

[shiva958]

Thank You. Will do this in the up-coming PR for threading.