Otel TracerProvider Embedding hard to auto-mock.

Description

There is a marker interface 'embedded.TracerProvider' with unexported methods https://pkg.go.dev/go.opentelemetry.io/otel/trace/embedded#TracerProvider

With a testify style mock, the Mock does not implement otel.trace.TracerProvider unless the generated code is edited to add that same embedded interface.

Perhaps there is another way of doing it; I'm not sure, but I thought you'd like to know :>

Having some way to add some code to the generated mock struct definition would perhaps be enough to solve this.