Bug fix: read ssh of extremum from shapefile

We need ssh of extremum in `set_contours`, to compute `innermost_level_2`.

Inst_eddies/Tests/examine_eddy.f90

@@ -10,7 +10,7 @@ program examine_eddy
 
   use config_m, only: config, min_radius
   use cont_list_m, only: create_cont_list, close_cont_list
-  use derived_types, only: snapshot, shpc_slice_handler, eddy, missing_ssh
+  use derived_types, only: snapshot, shpc_slice_handler, eddy
   use input_ssh_m, only: input_ssh, max_radius
   use read_eddy_m, only: read_eddy
   use shpc_create_m, only: shpc_create
@@ -109,7 +109,9 @@ program examine_eddy
   coord = coord * deg_to_rad
   e%extr%coord = coord(:, eddy_i_target)
   e%extr%coord_proj = nint(convert_to_ind(e%extr%coord, corner, step))
-  e%extr%ssh = missing_ssh ! because we do not care about this
+  call dbf_get_field_index_03(hshp, "ssh", ifield)
+  call dbf_read_attribute_03(e%extr%ssh, hshp, ifield, &
+       ishape = ishape_first + eddy_i_target - 1)
   e%cyclone = cyclone
 
   ! Define the geographical window around the target eddy extremum: