fix causality graph zoom not resetting
fix causality graph zoom not resetting

i think one of the differences between the causality and pipeline graph
is that the pipeline graph needs to retain the zoom/translate if the
pipeline config gets updated, no such concerns is needed for the
causality graph

Signed-off-by: Bohan Chen <c9a015a7f6482b47c219aa2cbd78ba6c88c0a327@pivotal.io>

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse