When trying to use `edit_binary_decoded` with an empty file, pysim
runs into a len(None) exception, because hpkl.to_dict()['hnet_pubkey_list'] returns
None.
Can reproduced with a CCC Camp 2023 usim and editing the file.
Change-Id: Ib8e322e65dd768bfd49e7a5620a2163f12a74ec7
Card.update_ust() got replaced by the file operation ust_update().
In addition to Change-Id I7a6a77b872a6f5d8c478ca75dcff8ea067b8203e
Fixes: f8d2e2ba08 ("split pySim/legacy/{cards,utils} from pySim/{cards,utils}")
Change-Id: Ie6405cae37493a2101e5089a8d11766fbfed4518