Update the way AMF/SMF/UPF/NRF process DNN (case insensitive) if necessary
According to Section 9.1(Structure of APN, which is DNN value) 3GPP TS 23.003, The case of alphabetic characters is not significant. We should verify AMF/SMF/UPF/NRF and update them if necessary.
Edited by Tien-Thinh Nguyen