typos in opentelemetry configuration

[arner]

The protocol for opentelemetry is called OTLP.

In core.yaml and the FSC codebase, it's called both optl and otpl. To the point where you have to:

tracing:
    provider: otpl
    optl:
      ...

This is quite confusing 😅.

Propose to change them to opentelemetry in core.yaml, and otlp where we want a shorthand in the code.