Add a unlessUsing option to the RemoveDependency recipe

[timtebeek]

A thought that had come up in an earlier discussion as a possible path forward for this would be to add a onlyIfNotUsing option to the RemoveDependency. It wouldn't be perfect by any means, but it could get some of the job done.

Slack Message

[timtebeek]

This has come up repeatedly in Slack, as people are looking ways to know if a dependency can (somewhat) safely be removed. A dependency can not always be safely removed even if not using a particular package explicitly, due to reflection and service loaded dependencies, but it's a start to offer something for those that want to conditionally remove a dependency.