feat: allow string as schema for paginatedswaggerdocs

[dariozachow]

fixes #1101

[ppetzold]

@vsamofal PTAL when you have a moment 🙏

[vsamofal]

@dariozachow as far as I understand you are trying to avoid a dto being added as an extra model, and just allow to pass a name of it in schema.

it's not a breaking change so we should be ok, but can you write tests with at least 1 success and 1 failed case (when schema won't be found)

[dariozachow]

don't think its that easy to write a failed case because the handling of the schema is done by the swagger lib. It just returns the string with the reference to the schema. So thats logic provided by the swagger lib. I can add a test though which takes a string

[dariozachow]

@vsamofal can you take a look again?

[dariozachow]

@ppetzold can you take a look?