fix: don't import all of pulumi and aws, rather use existing imports

[JanStevens]

In search of circular references I came across this one and it seems like an odd thing to do:

1. It's not done in any other part of the code base
2. All imports for aws where already there
3. asset as pulumiAsset is already being done elsewhere

It also seems "dangerous" to include all of pulumi and aws.

I guess eslint rules would help here but for now this should already potentially prevent any issues