RESTClient: Rename JSONResponsePaginator to JSONLinkPaginator

[burnash]

Background

Both JSONResponsePaginator and HeaderLinkPaginator derive from BaseNextUrlPaginator providing a pagination based on the extracted next url value.

Proposed change

To make naming of paginators consistent and better reflect their functionality, rename JSONResponsePaginator to JSONLinkPaginator.

Task

• Rename JSONResponsePaginator to JSONLinkPaginator in dlt/sources/helpers/rest_client
• Update tests
• Update the documentation