Yarn 1.x: Parse package.json to gather workspace metadata

[taylormadore]

Yarn 1.x yarn.lock files usually do not contain metadata for workspaces, so they will need to be parsed from package.json. Some inspiration for this change may be found in Cachito's yarn module.

Some examples of how workspaces are specified and under what conditions they are added to the lockfile can be found here: https://github.com/cachito-testing/cachito-yarn-workspaces

Acceptance criteria

• Workspace dependency metadata is parsed from package.json into dataclasses
• Adapt the cachito integration test for yarn workspaces
• Ensure that path dependencies leading outside the repo are detected and an exception is raised