[sdk-node] allow multiple spanProcessors/logProcessors to be configured

[hectorhdzg]

spanProcessors and logProcessors order is important when they are doing some modification of the actual span/log, allowing multiple ones will permit more specific scenarios.

[YunosukeY]

I think it would be nice if a metricReaders option is allowed as well.

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 14 days.

[github-actions]

This issue was closed because it has been stale for 14 days with no activity.

[trentm]

Please correct me if I'm wrong. This issue is still relevant for allowing multiple logProcessors.