Adding retries to AWS API calls

[biacar]

Proposed Changes

This PR addresses the issues related to transient errors while querying AWS APIs. Retries have been added to AWS API calls with a sleep time in between the calls to make sure whatever the error code returned by AWS is not transient. Credential errors are not retried.

The motivation behind this PR is unlock failures during peer discovery due to timed out AWS calls. The retries on the AWS calls would reduce the possibility of a node not releasing the discovery lock after successfully joining a cluster.

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• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
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[michaelklishin]

Merged manually.

[michaelklishin]

Backported to v3.9.x.

[michaelklishin]

Two cosmetic follow-up PRs: 59ebb83, 6bf4a99