Allow loading @opentelemetry/winston-transport dynamically

[harelmo-lumigo]

Is your feature request related to a problem? Please describe

Winston instrumentation assumes @opentelemetry/winston-transport is installed and attempts to resolve it using require, from a location adjacent to the application using Winston.
That limits the use-cases for packages wrapping the @opentelemetry/winston-instrumentation, as the transport cannot be provided via a different path or by some other dynamic loading method.

Describe the solution you'd like to see

Provide a constructor argument that will allow specifying the transport to be used, as an instance of OpenTelemetryTransportV3.

Describe alternatives you've considered

Alternatively, there can be either:

1. an env-var respected by the instrumentation that points to the path from which the transport can be loaded
2. a constructor argument with the path to load the transport from, instead of providing an instance
3. a constructor argument with a function through which a transport instance can be obtained

Additional context

None