@Override
    public List<ValidationEvent> evaluate(Differences differences) {
        List<ValidationEvent> events = new ArrayList<>();
        differences.changedShapes(EntityShape.class).forEach(change -> validateOperation(change, events));
        return events;
    }
A meta-validator that checks for the removal of an operation or
resource binding from a service or resource.

<p>A "RemovedOperationBinding" eventId is used when an operation is
removed, and a "RemovedResourceBinding" eventId is used when a
resource is removed.
smithy-diff/src/main/java/software/amazon/smithy/diff/evaluators/RemovedEntityBinding.java