Warnings for behaviour not implented in Elixir 1.17

[wkirschbaum]

   warning: function shift_date/4 required by behaviour Calendar is not implemented (in module Support.HoloceneCalendar)
    │
  1 │ defmodule Support.HoloceneCalendar do
    │ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    │
    └─ test/support/holocene_calendar.ex:1: Support.HoloceneCalendar (module)

    warning: function shift_naive_datetime/8 required by behaviour Calendar is not implemented (in module Support.HoloceneCalendar)
    │
  1 │ defmodule Support.HoloceneCalendar do
    │ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    │
    └─ test/support/holocene_calendar.ex:1: Support.HoloceneCalendar (module)

    warning: function shift_time/5 required by behaviour Calendar is not implemented (in module Support.HoloceneCalendar)
    │
  1 │ defmodule Support.HoloceneCalendar do
    │ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    │
    └─ test/support/holocene_calendar.ex:1: Support.HoloceneCalendar (module)

[mathieuprog]

Fixed