static string GetKeyStringCore(DiagnosisSubmissionParameter.Key k) => string.Join(".", k.KeyData, k.RollingStartNumber, k.RollingPeriod, k.ReportType);
static string GetKeyString(DiagnosisSubmissionParameter.Key k) => string.Join(".", k.KeyData, k.RollingStartNumber, k.RollingPeriod, k.TransmissionRisk);