Introducing the Experimental info() Function

Prometheus 3.0 introduces the experimental `info()` function to simplify enriching metrics with metadata labels from "info" metrics (like those from OpenTelemetry). Traditionally, this required complex PromQL join queries specifying join labels and data labels, but `info()` achieves the same result with a single function call, automatically handling label matching. Crucially, `info()` also resolves the “churn problem” – issues caused by changing info metric labels – by automatically selecting the latest time series data, resulting in more reliable queries and dashboards.