private static ValidationEvent changeSeverity(ValidationEvent event, Severity severity, String reason) {
        if (event.getSeverity() == severity) {
            return event;
        } else {
            // The event was suppressed so change the severity and reason.
            ValidationEvent.Builder builder = event.toBuilder();
            builder.severity(severity);
            if (reason != null) {
                builder.suppressionReason(reason);
            }
            return builder.build();
        }
    }
Creates a ValidationEventDecorator for the given Model.

<p>Validators, suppressions, and severity overrides found in the model are used each time
{@link ValidationEventDecorator#decorate(ValidationEvent)} is called. The
{@link ValidationEventDecorator#canDecorate(ValidationEvent)} always returns true.

@param model Model to load validation events from.
@return Returns a decorator that can be used to modify the severity and suppression reason of each given event.
smithy-model/src/main/java/software/amazon/smithy/model/validation/suppressions/ModelBasedEventDecorator.java