[java-spanner] Not able to see the metrics of port 4317

Hi Team,

I'm creating the SdkMeterProvider like below (referred from UserGuide)
```
SdkMeterProvider sdkMeterProvider = SdkMeterProvider.builder()
// Use Otlp exporter or any other exporter of your choice.
.registerMetricReader(PeriodicMetricReader.builder(OtlpGrpcMetricExporter.builder().build())
.build())
.build();
```

I'm able to create the spanner instance and my application is getting started, However, I do not see metrics on the default endpoint. When I run my application I see below log
```
2025-02-18T09:40:02.473-08:00 WARN 30365 --- [alhost:4317/...] i.o.exporter.internal.grpc.GrpcExporter : Failed to export metrics. Server responded with gRPC status code 2. Error message: Failed to connect to localhost/[0:0:0:0:0:0:0:1]:4317
```

The error message indicates that the OTLP GRPC Metric Exporter is unable to connect to the OpenTelemetry Collector on localhost:4317. This is the default port used by the OpenTelemetry Collector to receive metrics.

Is there any additional setting that I need to add so that the metrics would be exported correctly? I'm able to view the metrics when I use the Prometheus Exporter.