The get_dmrpp script needs to start indexing at 1 when picking a random variable

[eigenbeam]

In the get_dmrpp script's dap4_array_test function, it selects a random number in order to test a variable of a given type. It calls dap4_array_dim_counter which selects the variable, but that function assumes that the match_num variable starts at 1. So if 0 is passed, it won't select a random variable and will result in an error.