Allow user to provide with additional GRPC interceptors

[evgeniy-b]

It would be great to have a possibility to provide with own interceptors for service initialization since there is currently no way to inject there. Ideally (or additionally) in a global manner so this could be configured without modifying client/service initialization code and interceptor could be injected dynamically in tests (to fake requests).

[evgeniy-b]

Any news on this?

[fables-tales]

@evgeniy-b thanks for your feature request.

This is something we're going to look at hollistically as part of all of our libraries, not just the ruby library. As such, our team has to consider the design for this to make sure it makes sense for all of our libraries, is documented, etc.

We'll for sure ping back on this issue once we've started work on this.