5034: Update Workbench integration tests.

5034: Update Workbench integration tests.

A lot of tests started failing because

* they were looking for the string "content hash" to assert they were
  on a collection page, or
* they expect the portable data hash to be real text on the page (as
  opposed to the value of an <input>).

Fixes:

* Have the upload test check that the collection is empty by looking
  for the relevant size information, which was specified by the story.
* Make sure we're on a specific collection page by looking for the
  collection's name or UUID (depending on what's available).
* Refute we're on a specific collection page by matching against the
  URL.  This seems much safer in the long run.
* Remove the "Content hash" assertion from projects test altogether.
  The prior text assertion should be sufficient to ensure we're on the
  right page.

Refs #5034.