Maybe rethink cdkDependencies in awscdk-construct

[Miradorn]

Hi there and thanks for the great project!

We're currently building https://github.com/superluminar-io/super-eks/ with it and are very happy.

Unfortunately we're either doing smth wrong or there might be a conceptual problem in the way cdkDependencies are handled.
The Problem (and solution i think) is described in this blogpost https://dev.to/udondan/correctly-defining-dependencies-in-l3-cdk-constructs-45p , basically: defining cdk deps as real dependencies puts limitations on your downward consumers, therefore they should be added to peerDependencies and devDependencies, as this enables to use them during development but allows consumers to use their own specified version.

If this is correct thinking on my side, this line https://github.com/projen/projen/blob/main/src/awscdk-construct.ts#L150 would probably has to be changed? Or is there another way that I sould be using? Also the comment (and therefore reasoning) above the method is probably outdated, since npm 7 is actually installing peerDependencies (https://github.blog/2021-02-02-npm-7-is-now-generally-available/#peer-dependencies)

If you're agreeing with me I can submit a PR if you'd like.
Thanks again!

[eladb]

At the moment we add deps as both "peer" and normal deps since previous versions of npm did not install peer dependencies automatically. This means that users would need to manually add all the transitive deps to their projects.

This will be solved once we released CDK 2.0 which will be published as a single module, so libs could just define it as a peer dep and consumers will bring the correct version.

Happy to accept a contribution to add a switch which disables this behavior though, especially given its a hack.