@Nullable
    @Deprecated
    protected final BiFunction<? super RequestContext, ? super Throwable, ? extends @Nullable Object>
    responseCauseSanitizer() {
        return null;
    }
Don't use this method. null is always returned.

@deprecated Deprecated for removal in the next major version.
core/src/main/java/com/linecorp/armeria/common/logging/LoggingDecoratorBuilder.java