It would be nice if SpanBuilder had the same `setAttribute(AttributeKey<Long> key, int value)` convenience method as Span: https://github.com/open-telemetry/opentelemetry-java/blob/6c0d140dff4b5fd6e168e6b6a65edf4cf73c7571/api/all/src/main/java/io/opentelemetry/api/trace/Span.java#L169-L171