When an attribute value changes in sensitivity, we previously rendered
this in the diff with a `~` update action and a note about the
consequence of the sensitivity change. Since we also suppress the
attribute value, this made it impossible to know if the underlying value
was changing, too, which has significant consequences on the meaning of
the plan.
This commit adds an equality check of the old/new underlying values. If
these are unchanged, we add a note to the sensitivity warning to clarify
that only sensitivity is changing.
5fc3ba37a6