Fix remaining tests not using chain_spec in method refactors

apps/contract-migration/scripts/import_users.py

@@ -124,10 +124,6 @@ def register_eth(i, u):
     return address
    
 
-def register_ussd(u):
-    pass
-
-
 if __name__ == '__main__':
 
     #fi = open(os.path.join(user_out_dir, 'addresses.csv'), 'a')
@@ -155,8 +151,6 @@ if __name__ == '__main__':
             sub_chain_str = '{}:{}'.format(chain_spec.common_name(), chain_spec.network_id())
             u.identities['evm'][sub_chain_str] = [new_address]
 
-            register_ussd(u)
-
             new_address_clean = strip_0x(new_address)
             filepath = os.path.join(
                     user_new_dir,