Check if hosts file contains non ASCII characters

[wtmpx]

If the /etc/hosts contains ä , Ö , ü or similar , the migration will fail.

Apr 10 09:39:31 localhost.localdomain suse-migration-prepare[1875]: File "/usr/lib/python3.13/site-packages/suse_migration_services/units/prepare.py", line 145, in perform
Apr 10 09:39:31 localhost.localdomain suse-migration-prepare[1875]: contents = fp.read()
Apr 10 09:39:31 localhost.localdomain suse-migration-prepare[1875]: File "", line 325, in decode
Apr 10 09:39:31 localhost.localdomain suse-migration-prepare[1875]: UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe4 in position 8032: invalid continuation byte

https://forums.suse.com/t/upgrading-from-sles15-sp7-to-sles-16-0-failed/46208/40?u=aalzayed

the suse-migration-pre-checks should warn the user. Simply check will show the broken lines:
grep -axv '.*' /etc/hosts