Feature request: dry run mode to show full path and result of create/update

[nitrocode]

A dry run mode would be very handy. Especially because secrets in secretsmanager take 7 days to delete.

For example, I'm using the secrets backend and I use this to write.

chamber -b secretsmanager write "service" "datadog" -- "value"

This creates service name with a datadog=value which would be nice to know before writing/updating it.

$ chamber -b secretsmanager write --dry-run "service" "datadog" -- "value"

dry-run detected
Would create "arn:aws:secretsmanager:us-east-1:123456789012:secret:service-??????" with datadog=value

This way, I would then know to do the following

$ chamber -b secretsmanager write --dry-run "service/datadog" "api_key" -- "value"

dry-run detected
Would create "arn:aws:secretsmanager:us-east-1:123456789012:secret:service/datadog-??????" with api_key=value