Fix tuist generate when a binary SPM dependency is removed

[fortmarek]

Resolves #6263

Short description 📝

As described in the attached issue, tuist generate fails after running tuist install when a dependency was removed.

This is because swift package resolve does remove the reference to the binary in the .build/workspace-state.json file, but the following is kept:

      {
        "basedOn" : null,
        "packageRef" : {
          "identity" : "paypalcheckout-ios",
          "kind" : "remoteSourceControl",
          "location" : "https://github.com/paypal/paypalcheckout-ios",
          "name" : "paypalcheckout-ios"
        },
        "state" : {
          "checkoutState" : {
            "revision" : "da1b998dcab91011b05df139a6819cc58dd45ccd",
            "version" : "1.3.0"
          },
          "name" : "sourceControlCheckout"
        },
        "subpath" : "paypalcheckout-ios"
      }

This means that we still try to parse the paypalcheckout-ios package (even though it was removed from Package.swift) but we would no longer find a binary for it.

To handle this more gracefully, we try to use a default path for the binary. If the target is not referenced by any downstream target, the generation will succeed. If the target is referenced, the generation will fail with an error that the binary could not be found.

How to test the changes locally 🧐

• Go to fixtures/ios_app_with_spm_dependencies fixture
• Add .package(url: "https://github.com/paypal/paypalcheckout-ios", from: "1.3.0"), to Tuist/Package.swift
• Run tuist install && tuist generate
• Comment out the newly added line
• Run tuist install && tuist generate again -> the generation should fail with the latest tuist release and it should succeed with the changes in this PR

Contributor checklist ✅

• The code has been linted using run mise run lint:fix
• The change is tested via unit testing or acceptance testing, or both
• The title of the PR is formulated in a way that is usable as a changelog entry
• In case the PR introduces changes that affect users, the documentation has been updated

Reviewer checklist ✅

• The code architecture and patterns are consistent with the rest of the codebase
• Reviewer has checked that, if needed, the PR includes the label changelog:added, changelog:fixed, or changelog:changed, and the title is usable as a changelog entry

[pepicrft]

Thanks Apple for continuing to make developers' life harder every day 😆