Cache test data on Azure Pipelines (#438)
Cache test data on Azure Pipelines (#438)

Needed because Windows on Azure Pipelines can't fetch data from https://oceania.generic-mapping-tools.org/. Includes @earth_relief_10m, @earth_relief_60m, @ridge.txt, @Table_5_11.txt , @tut_bathy.nc, @tut_quakes.ngdc, and @tut_ship.xyz.

Co-authored-by: Dongdong Tian <3eae6d0b95aef6af8a0d785fe9f127268703c43c@gmail.com>
GenericMappingTools/gmt-python,GenericMappingTools/gmt-python