Remove Page#update_assets

Only caller left was the sort_images action removed last commit.
Kept alive only as a test-setup convenience for diff_against
coverage, which is what it actually was -- an implicit API with no
deliberate contract, sitting there for anyone to call. Rewrote the
one test to set up its fixture state directly via related_assets
rather than through a method whose real job was already done.

0 files changed, 0 insertions, 0 deletions