Open API schema is missing info/title and version

via SUPPORT-14182, info/title and version are indeed required in open api spec, resulting in failure to import the spec in 3rd-party tools like Postman.

Steps to reproduce

1. Get url for openapi.json from magnolia: /.rest/openapi.json
2. Import in postman and get an error

> Error while importing: format not recognized

Workaround

Download openapi.json and modify it adding info with title and version

Development notes

I assume you have to add the info here

https://git.magnolia-cms.com/projects/MODULES/repos/rest/browse/magnolia-rest-tools/src/main/java/info/magnolia/rest/tools/SwaggerRestDispatcherServlet.java#119