Prometheus bridge: Verify that prometheus start timestamps are working correctly

[dashpole]

Problem Statement

Now that support for creation timestamps exists in the promethues client, we should update to the latest version of the client, and verify that creation timestamps are working as expected.

https://github.com/prometheus/client_golang/releases/tag/v1.17.0

prometheus/client_golang#1313

Proposed Solution

This should be done with a new unit test.

[hiroyaonoe]

I want to work on this issue.
I read these.

• Extend Counters, Summaries and Histograms with creation timestamp prometheus/client_golang#1313
• (feat): Add created timestamps to counter, summary and histogram prometheus/client_model#66
• https://github.com/ArthurSens/proposals/blob/ab2516375639ea69305bbefe8974d7cc91d71cf9/proposals/2023-06-13_created-timestamp.md
• https://pkg.go.dev/go.opentelemetry.io/contrib/bridges/prometheus

I'll add and update unit tests in https://github.com/open-telemetry/opentelemetry-go-contrib/blob/main/bridges/prometheus/producer_test.go