Mutable content dependency removal by convert is ordering dependent

Following SLING-8649, the converter is trying to remove dependencies on mutable content package from converted packages. That suffers from an ordering problem as it will only learn about mutable content package ids when it hits the package but removes the dependencies directly when it is converting a package.

In other words, if a content package contains two sub packages, one mutable and one immutable and the immutable package has a dependency on the mutable one it will depend on the order they are found in the content package whether the dependency is removed or not.