Add support for S3 events in a separate AWS account

When testing a lambda connecting to S3 bucket event, I got the following error:
chalice.deploy.deployer.ChaliceDeploymentError: ERROR - While deploying your chalice application, received the following error:

The bucket is created in a different AWS account. Is the cross account bucket supported?

Start by reproducing the reported ChaliceDeploymentError while configuring a Lambda for an S3 bucket event in another AWS account. Trace the deployment path that validates the bucket account and determine the AWS permissions and behavior required for cross-account support. Done means the configuration deploys successfully without this error, with coverage for the cross-account case.

Written by the indexing model from the issue text.