patch 8.2.1287: Vim9: crash when using an imported function

Problem:    Vim9: crash when using an imported function.
Solution:   Add the function type to the imported entry. (closes #6522)
diff --git a/src/vim9script.c b/src/vim9script.c
index 34c3dab..784283e 100644
--- a/src/vim9script.c
+++ b/src/vim9script.c
@@ -465,7 +465,10 @@
 		imported->imp_var_vals_idx = idx;
 	    }
 	    else
+	    {
+		imported->imp_type = ufunc->uf_func_type;
 		imported->imp_funcname = ufunc->uf_name;
+	    }
 	}
     }
 erret: