dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm

While running the test suite there's a number of warnings:

dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 90.
dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 150.
dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 153.
...
dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 563.
dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 670.
dump() better written as CORE::dump() at lib/DateTime/Format/RelativeTime.pm line 775.

And some tests also fail --- not sure if this is in any way related to the warnings:

Can't locate object method "_message" via package "DateTime::Format::RelativeTime" at lib/DateTime/Format/RelativeTime.pm line 53.