Fixes two data product related tests

register_dataset no longer takes advantage of the registered attribute
for a dataset resource, so the test no longer needs to verify that.

activate_data_product on a derived data product is now automatic during
creation. Calling activate_data_product on a derived data product
results in a BadRequest being raised, so this test got patched.
Merge pull request #1341 from lukecampbell/erddap

Fixes two data product related tests