it looks like (on Swift 6.0.3 at least) that SwiftPM eagerly clones all transitive package dependencies if just one product from that package is included in the build, even if that product depends on none of those repositories.
this means if product A in the root package depends on product B from swift-b, and something else in swift-b (like a test or an overlay) depends on swift-c, that the entire history for swift-c will be downloaded during the build for A.
is this a known issue with SwiftPM?