Rework paths in Cradle Dependencies

[fendor]

Original issue: https://github.com/digital-asset/ghcide/issues/633

The dependencies could be relative to the cradleRootDir or to componentRootDir e.g.

.
├── cabal.project
├── servant-server
│   └── servant-server.cabal
└─── servant-docs
    └── servant-docs.cabal

Options for 'servant-server'
Root directory:      ./servant
Component directory: ./servant/servant-server
Dependencies:        stack.yaml servant-server.cabal package.yaml

Options for 'servant-docs'
Root directory:      ./servant
Component directory: ./servant/servant-docs
Dependencies:        stack.yaml servant-docs.cabal package.yaml

We need to reload both components in case of change to ./servant/stack.yaml but only one for changes to ./servant/servant-server/servant-server.cabal, ./servant/servant-server/package.yaml and ./servant/servant-docs/servant-docs.cabal, ./servant/servant-docs/package.yaml respectively.

A proposed solution:
Change the API of cradle dependencies in hie-bios to give absolute paths since this is the only location where we can know this. (Another breaking change, yay)
Unfortunately, this does not play nicely with the latest breaking change to extend a CradleError with the dependencies of the component, since we dont know the component dir in that case :(

[fendor]

The simpler solution (and non backwards-compatibility breaking) would be to fix the returned dependencies.