Removed declaration of unused variable, s3, in mpas_test_remove_not_found.

Author: Andy Stokely

src/core_test/mpas_test_core_stream_list.F

@@ -273,7 +273,7 @@ end subroutine mpas_test_remove_from_empty_list
    subroutine mpas_test_remove_not_found(err)
       integer, intent(out) :: err
       type(MPAS_stream_list_type), pointer :: list, removed
-      type(MPAS_stream_list_type), pointer :: s1, s2, s3
+      type(MPAS_stream_list_type), pointer :: s1, s2
       integer :: ierr
 
       err = 0