[Feature] It would be good to have an OpenAPI to JSON schema comverter

[GeorgeFischhof]

Hi,

Is your feature request related to a problem? Please describe. Right now I have to generate JSON schemas from OpenAPI spec files. I do not how typical this issue is, but every part exist in datamodel code generator, just need to be tied together.

Describe the solution you'd like if --output-model-type equals to json-schema it should generate the JSON schemas for all top level objects in the response. Perhaps --output would select only one object.

Describe alternatives you've considered a new filter for the objects

BR, George