[chore] processor/metricsgenerationprocessor: migrate feature gate to mdatagen#47512

mx-psi merged 5 commits into

open-telemetry:mainopen-telemetry/opentelemetry-collector-contrib:mainfrom

ogulcanaydogan:refactor/46116-migrate-featuregate-metricsgenerationprocessorogulcanaydogan/opentelemetry-collector-contrib:refactor/46116-migrate-featuregate-metricsgenerationprocessorCopy head branch name to clipboard