Broken links about OpenTelemetry in README

[Delapouite]

Hi.

Currently, in the first paragraph of the README.md:

This solution is based on OpenTelemetry, to learn more about OpenTelemetry concepts, see the OpenTelemetry overview or OpenTelemetry FAQ.

Both links points to 404 document.

Looking at the Git history, I'm not quite sure where they used to lead.

Thanks.

[JacksonWeber]

@Delapouite Thank you for catching this! Links will be checked for correctness and updated.