Update opentelemetry version, adapt to breaking changes

[JT117]

Updated the opentelemetry, opentelemetry_sdk, opentelemetry-semantic-conventions from 0.26 to 0.27 and tracing-opentelemtry from 0.27 to 0.28.

I had to adapt certain part of the code to handle breaking changes, most notable:

• the opentelemetry::Value enum is now marked as non_exhaustive forcing a catch all match arm
• the TraceProvider::tracer_builder method has been removed, I use instead the tracer_with_scope

[abdolence]

Thanks for the contributions and notes about your changes here as well 👍🏻