Register user-provided SdkLoggerProvider and SdkMeterProvider on the OpenTelemetry bean

[mhalbritter]

We currently have auto-configuration for tracing via OpenTelemetry, by providing a SdkTracerProvider and ContextPropagators bean, which get registered on the OpenTelemetry bean.

OpenTelemetry supports metrics and logging, too. At the moment we don't want to auto-configure full support for that, but we should register the SdkLoggerProvider and SdkMeterProvider on the OpenTelemetry bean if they are in the application context.

This makes it easier for users who supply those beans themselves.

[mhalbritter]

I sketched something here: ccf9fc7