joda-time: Null pointer exeption may lead to DoS

Joda Time v2.12.5 was discovered to contain a NullPointerException via the component org.joda.time.format.PeriodFormat::wordBased(Locale). NOTE: this is disputed by multiple third parties who believe there was not reasonable evidence to determine the existence of a vulnerability. The submission may have been based on a tool that is not sufficiently robust for vulnerability identification.