René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Support references to non-object types","articleBody":"**Describe the bug**\r\nroot component schemas do not get parsed correctly, resolved to None\r\n\r\n**To Reproduce**\r\nSteps to reproduce the behavior:\r\n`openapi-python-client generate --path path_to_test.yaml`\r\n\r\n**Expected behavior**\r\nThe generated model Link should have `href: Union[Unset, str] = UNSET` as attribute\r\ninstead we have `href: Union[Unset, None] = UNSET`\r\n\r\n**OpenAPI Spec File**\r\n```\r\nopenapi: 3.0.0\r\n\r\ninfo:\r\n  version: '1'\r\n  title: 'test file'\r\n  description: 'description'\r\n\r\npaths: {}\r\n\r\ncomponents:\r\n  schemas:\r\n    Link:\r\n      type: object\r\n      properties:\r\n        href:\r\n          Uri:\r\n            type: string\r\n```\r\n\r\n**Desktop (please complete the following information):**\r\n - OS: Ubuntu 20.04\r\n - Python Version: 3.8.5\r\n - openapi-python-client version: up to date with main\r\n\r\n**Additional context**\r\n\r\nI am trying to build a 5g stack with the open source 5g api. This file in particular contains a lot of components schemas that get resolved to None\r\n\r\nhttps://github.com/jdegre/5GC_APIs/blob/master/TS29571_CommonData.yaml\r\n\r\nFor example the `Uri` components is translated to \r\n```\r\n@attr.s(auto_attribs=True)\r\nclass Uri:\r\n    \"\"\"  \"\"\"\r\n\r\n    additional_properties: Dict[str, Any] = attr.ib(init=False, factory=dict)\r\n```\r\nwhich does not seem right as it is only a `type:string` component\r\n","author":{"url":"https://github.com/p1-alexandrevaney","@type":"Person","name":"p1-alexandrevaney"},"datePublished":"2021-03-31T12:24:54.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/371/openapi-python-client/issues/371"}