Create an Ecto.UTCDateTimeRange from two ISO8601 strings.

Example

iex> import Ecto.DateTimeRange, only: [sigil_t: 2]
...>
iex> ~t(2020-02-02T00:01:00Z..2020-02-02T00:01:01Z)
%Ecto.DateTimeRange.UTCDateTime{start_at: ~U[2020-02-02T00:01:00Z], end_at: ~U[2020-02-02T00:01:01Z]}
...>
iex> ~t(2020-02-02T00:01:00Z..2020-02-02T00:01:01Z)U
%Ecto.DateTimeRange.UTCDateTime{start_at: ~U[2020-02-02T00:01:00Z], end_at: ~U[2020-02-02T00:01:01Z]}
...>
iex> ~t(2020-02-02T00:01:00..2020-02-02T00:01:01)N
%Ecto.DateTimeRange.NaiveDateTime{start_at: ~N[2020-02-02T00:01:00], end_at: ~N[2020-02-02T00:01:01]}
...>
iex> ~t(00:01:00..00:01:01)T
%Ecto.DateTimeRange.Time{start_at: ~T[00:01:00], end_at: ~T[00:01:01]}
...>
iex> ~t(hi there)
** (ArgumentError) Unable to parse DateTime(s) from input