Remove shapefile creation for PG tests

ci/test_mapserver_image.sh

@@ -289,7 +289,6 @@ run_basic_postgres_tests() {
     start_postgres
     start_pg_test_container
     gtiff_fn="/data/$(create_fake_geotiff)"
-    add_shapefile_content "${gtiff_fn}"
     add_postgres_projections
     add_postgres_tables
     add_postgres_content "${gtiff_fn}"