Adapt tests to change from simple_product to base_product in spree

[luisramos0]

Description

enterprise caching Spec is using simple product that has now ben transformed into an extension of BaseProduct with stock location.
See here:
spree/spree@14f911e91

Expected Behavior

Pass the test:
context "key-based caching invalidation" do
describe "is touched when a(n)" do
describe "with a supplied product" do

Actual Behavior

Broken test.

Steps to Reproduce

Run the spree branch build.

Severity

spree upgrade

Your Environment

spree branch

Possible Fix

replace simple_product with base_product