Add support for scoped packages within monorepos

[sfc-gh-jlai]

This change fixes how NPM dependencies are determined within a monorepo. At the moment, a scoped package will fail to be associated with the correct package when that dependency is not defined at the root of the workspace.

The reason for this is within the isNpmDependency method, we would interrogate the package name by splitting the package on /, and evaluate only the first slice. This is deal for packages like lodash which export multiple subpackages(?), however, this is not ideal for scoped packages (such as @emotion/react), as there is no @emotion package defined in package.json.

This behavior would implicitly work for workspaces where the dependency was defined at the a root package.json, since the isNpmPackage would fall through to its default return, which wouldn't include the npmLabel (the package name). However, this doesn't work in typical monorepos where dependencies are defined in projects further up from root.

The solution introduced is straightforward, to simply evaluate the original import statement if the evaluation of the first slice has fallen through. We perform this for both dependencies and devDependencies.

[sfc-gh-jlai]

@ewianda Pinging on this one