fix(collect-dependents): Avoid skipping dependents of cyclic dependencies

[fresk-nc]

In case of cyclic dependencies, some packages of the modified package are skipped.

Description

packages:

package-cycle-1
  localDependents:
    package-cycle-2
    package-cycle-extraneous-1
    package-cycle-extraneous-2

package-cycle-2
  localDependents:
    package-cycle-1
    package-cycle-extraneous-2

Let's say we changed package-cycle-2 then the following will happen:

1. package-cycle-2 is current node. Check local dependents of package-cycle-2
2. Check package-cycle-1
3. Add package-cycle-1 to changed. Remember that we visit it.
4. Dive to the level below. Check local dependents of package-cycle-1
5. Skip package-cycle-2 because it is current node. Remember that we visit it.
6. Skip package-cycle-extraneous-1 because local dependents of package-cycle-1 include package-cycle-2. Remember that we visit it.
7. Skip package-cycle-extraneous-2 because local dependents of package-cycle-1 include package-cycle-2. Remember that we visit it.
8. Back to the level above. Check package-cycle-extraneous-2 and skip because we have visited it.

So, we missed package-cycle-extraneous-2 and it looks like a bug.

I replaced depth-first search to breadth-first search. Now it works well.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[kenrick95]

Please excuse me on commenting on old PR, but what is the reason behind ignoring package-cycle-extraneous-1? I know it is directly because siblingDependents.has(currentNode.name) evaluates to true, but what is the intention behind this? I don't fully understand the comment there ("a direct or transitive cycle, skip it"). I hope someone could explain this. Thanks