With hash equivalence working properly, this test breaks as it detects
an unchanged tasks and doesn't rerun subsequent tasks.
Add a uuid to the payload to ensure it doesn't ever match
equivalence and the test works as intended.
(From OE-Core rev: d19873b6b5d0068f857a8f9f3686729ba4e67f0f)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>