Add support for Falcon Snapshot

[kuhnskc]

Hello team,

We need to add support for Falcon Snapshot image as well. The Snapshot image exists in the CrowdStrike registry and customers must push it into their ECR. The image URI is then referenced in the CloudFormation stack to onboard Snapshot. Here is the link to our documentation on pulling the image manually.

https://falcon.crowdstrike.com/documentation/page/c8b31ee8/enable-snapshot-management#j985db7c