We're currently being intentionally cautious about adding too many tests
while these new parts of the system are still evolving and changing a lot,
but the execGraphBuilder behavior is hopefully self-contained enough for
a small set of basic tests to be more helpful than hurtful.
We should extend this test, and add other test cases that involve more
complicated interactions between different resource instances of different
modes, once we feel that these new codepaths have reached a more mature
state where we're more focused on localized maintenance than on broad
system design exploration.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
