@Test void report_trace() throws IOException {
    callReport(grpcRequest); // Result is effectively void

    awaitSpans();

    assertThat(storage.getTraces())
      .containsExactly(TestObjects.TRACE);
  }
This tests that we accept messages constructed by other clients.
zipkin-server/src/test/java/zipkin2/server/internal/ITZipkinGrpcCollector.java