Write to standard output instead of standard error

See commit f5e0f59e.

Inst_eddies/Tests/test_mean_speed.f90

 program test_mean_speed
 
-  use, intrinsic:: ISO_FORTRAN_ENV
-
   ! Libraries:
   use gpc_f, only: shp_read_pol, polygon
   use jumble, only: get_command_arg_dyn
@@ -38,8 +36,8 @@ program test_mean_speed
   !---------------------------------------------------------------------
 
   call get_command_arg_dyn(1, contour_filename, "Required argument: shapefile")
-  write(unit = error_unit, nml = main_nml)
-  write(unit = error_unit, fmt = *) "Enter namelist main_nml."
+  write(unit = *, nml = main_nml)
+  print *, "Enter namelist main_nml."
   read(unit = *, nml = main_nml)
   write(unit = *, nml = main_nml)