in Sources/apm-agent-ios/Session/SessionSampler.swift [66:73]
init(_ sampleRateResolver: @escaping () -> Double) {
self.sampleRateResolver = sampleRateResolver
super.init()
NotificationCenter.default.addObserver(
self, selector: #selector(handleSessionChange), name: .elasticSessionManagerDidRefreshSession,
object: nil)
}