Problem Statement

Support array of AnyValue per https://opentelemetry.io/docs/specs/otel/common/#anyvalue

Proposed Solution

Add SLICE type to https://pkg.go.dev/go.opentelemetry.io/otel/attribute

Prior Art

#6809

_{Tip: React with 👍 to help prioritize this issue. Please use comments to provide useful context, avoiding +1 or me too, to help us triage it. Learn more here.}