Package assembly issues with AboutFileHandler

[tdruez]

@JonoYang I'm getting 6 "DiscoveredPackage matching query does not exist" errors in the assemble_package step running the scan_codebase pipeline with the following input:
https://files.pythonhosted.org/packages/63/a8/f1566bfa76158f1088baf2b3e37bf0aba43666e182d63cd066ceed61699c/python_inspector-0.6.4-py3-none-any.whl

Those errors seems to all be related to the AboutFileHandler:

[JonoYang]

@tdruez Looks like AboutFileHandler.assemble() is trying to assign a Resource to a Package before the Package is created in scancode.io. I've updated the code in AboutFileHandler.assemble() to yield Packages before assigning them to a Resource in aboutcode-org/scancode-toolkit#3115

[tdruez]

@JonoYang thanks for the fix! Could you double check all the FileHandler.assemble() to make sure the Packages are properly yield before Resources?

[JonoYang]

@tdruez All assemble() methods of Package handlers in packagedcode yields Packages before Dependencies and Resources. Closing this now that we are using a scancode-toolkit version with these changes.