Cache the 03s earth relief tile @N35E135.earth_relief_03s_g.nc (#985)

Co-authored-by: Dongdong Tian <[email protected]>

Author: core-man

.github/workflows/cache_data.yaml

@@ -34,6 +34,11 @@ jobs:
                         @earth_relief_30m_p @earth_relief_30m_g \
                         @earth_relief_01d_p @earth_relief_01d_g \
                         @earth_relief_05m_p @earth_relief_05m_g
+          # Download one tile of the 03s srtm data.
+          # @N35E135.earth_relief_03s_g.nc is for internal use only.
+          # The naming scheme may change. 
+          # DO NOT USE IT IN SCRIPTS.         
+          gmt which -Ga @N35E135.earth_relief_03s_g.nc
           gmt which -Ga @ridge.txt @Table_5_11.txt @test.dat.nc \
                         @tut_bathy.nc @tut_quakes.ngdc @tut_ship.xyz \
                         @usgs_quakes_22.txt