TST: Separate remote and non-remote tests in docs/coordinates/index.rst #14646

.. doctest-remote-data::

    >>> loc = EarthLocation.of_address('Tucson, AZ')
    >>> from timezonefinder import TimezoneFinder
    >>> tz_name = TimezoneFinder().timezone_at(lng=loc.lon.degree,
    ...                                        lat=loc.lat.degree)
    >>> tz_name
    'America/Phoenix'

The resulting timezone name could then be used with any packages that support
time zone definitions, such as the (Python 3.9 default package) `zoneinfo
<https://docs.python.org/3/library/zoneinfo.html>`_:

.. doctest-remote-data::

    >>> import datetime
    >>> from zoneinfo import ZoneInfo
    >>> tz = ZoneInfo(tz_name)
    >>> dt = datetime.datetime(2021, 4, 12, 20, 0, 0, tzinfo=tz)