Fix dep of artifact dep same deactivated target

[elchukc]

What does this PR try to resolve?

Fixes cargo tree -Z bindeps panic in 10593 (comment).

• a dependency of an artifact dependency is platform specified
• artifact dep itself is { target = } with the same platform as its own dependency
• the platform is not activated.

Essentially, no entry found for key happens because artifact deps for deactivated platforms are not properly filtered out when adding a package to the graph. Adding --target all to cargo tree -Z bindeps makes this bug go away.

As I understand, expected behaviour is to treat artifact deps like any other dep and only include ones targeting the host platform unless specified in --target <triple>.

i.e. if bar is the artifact dep, we expect cargo tree -Z bindeps to output:

foo v0.1.0 ([ROOT]/foo)

While cargo tree -Z bindeps --target all outputs:

foo v0.1.0 ([ROOT]/foo)
└── bar v0.1.0 ([ROOT]/foo/bar)
    └── baz v0.1.0 ([ROOT]/foo/baz)

How should we test and review this PR?

Test case changed in this PR is sufficient.

Additional information

This bugfix is separate from implementing the design changes in issue this [comment], which is still WIP.