Feature Request: SSM/KMS region configuration

[virgilwashere]

🚸 improve SSM/KMS region configuration UI

• "KMS: same as SSM region"

Default to using SSM region config for KMS, with a checkbox that toggles the input box.

• Use a dropdown list for region, with direct input override

The list of regions is a defined dataset. You can even query it via Parameter Store....see #54

[smblee]

This is a good idea. Thanks for the input! (PR is always welcome :) )