csv_export2 does not work with dates beyond year 2262

[berland]

Describe the bug
csv_export2 will crash if it encounters summary files containing dates beyond the year 2262. This is a limitation from fmu-ensemble which again inherits the limitation from pandas.

The bug is part of the documentation, remove when resolved (inside csv_export2.py)

Expected behavior
No error.

Workaround
Users can use ECL2CSV (from ecl2df) as a forward model, and merge_csv (subscript) as a workflow.

Possible resolution
fmu-ensemble can use ecl2df to parse the summary files, which is able to workaround the 2262-issue in pandas:
See equinor/fmu-ensemble#182 (stale)

Alternatively, fixing equinor/resdata#804 might also suffice. EDIT: It did not.