Add version info to prometheus metrics

[ClifHouck]

Addresses triton-inference-server/server#6320

Example metric output:
$ curl -s --request GET "http://localhost:8002/metrics" | grep api triton_version_information{api_major_version="1",api_minor_version="16",server_major_version="1",server_minor_version="24"} 0

[dyastremsky]

Thanks for contributing this! Have you submitted a CLA yet?

[ClifHouck]

Thanks for contributing this! Have you submitted a CLA yet?

I think the CLA finally got sorted. I should be good to go.

[ClifHouck]

@dyastremsky Is there anything I can do to further this PR?

[dyastremsky]

Thank you for submitting your CLA, Clif! Apologies for the delay.

Ryan and Olga, do these look good to you? The original issue mentioned exposing the version info via Prometheus as one way of addressing the need to see Triton version info. Do we want these to be accessible via Prometheus?

[rmccorm4]

Hi @ClifHouck, thanks for the contrbution.

I reached out on the original issue to clarify the ask - I'm not sure if server/backend API versions are necessary for the original ask if the actual triton release version is reflected and can be mapped.

However, it does raise a question that this extra level of detail may be useful to add to an existing endpoint. Do you have any reasoning on exposing these through prometheus rather than another existing REST endpoint? Pros of adding it to a standard (non-metrics) endpoint is that it would always be available, regardless of whether the server was built or configured at runtime to use prometheus metrics or not.