Move collection UI e2e test from datajson to catalog app

[jbrown-xentity]

User Story

In order to have confidence in the collection ui components built across multiple CKAN extensions, data.gov team wants to move the unit test in ckanext-datajson to an integration test on catalog app.

Acceptance Criteria

[ACs should be clearly demoable/verifiable whenever possible. Try specifying them using BDD.]

• GIVEN datasets are created in the catalog app that are related via collections
  WHEN the dataset page is visited happens
  THEN the page contains a button to search through the collection
  AND the search of collections works with the correct number of datasets

Background

Due to logic being separated in multiple ckan extensions (geodatagov and datajson), we want to test this at the application level. This will allow us to remove the ckanext-datajson tests from here, which are causing blockers.

Security Considerations (required)

None

Sketch

Create datasets that are part of a collection, and then evaluate dataset and search pages.
Use test similar to this one
Make sure to upgrade/update ckanext-datajson library.