message: fix redundant pkgid generation
diff: @@ -11,7 +11,7 @@ use cargo::core::Resolve;
  use cargo::core::{Dependency, PackageId, Registry, Summary};
  use cargo::util::{CargoResult, Config, ToUrl};
  -use proptest::collection::{btree_map, btree_set, vec};
  +use proptest::collection::{btree_map, vec};
  use proptest::prelude::*;
  use proptest::sample::Index;
  use proptest::strategy::ValueTree;
  @@ -336,8 +336,8 @@ pub fn registry_strategy(
  let allow_deps = prop::bool::weighted(0.99);
  let list_of_versions =
  - btree_set((raw_version, allow_deps), 1..=max_versions).prop_map(move |ver| {
  - ver.iter()
  + btree_map(raw_version, allow_deps, 1..=max_versions).prop_map(move |ver| {
  + ver.into_iter()
  .map(|a| (version_from_raw(&a.0), a.1))
  .collect::<Vec<_>>()
  });
  