base: ensure migrated persons have a user_id

Persons created before the introduction of ERP5 Login and user_id will only
have a user_id after migration if they were already user before migration,
otherwise they will not have a user_id and creating assignments and ERP5 Login
for this person creates a user which can not log in the system.

To make it possible for these persons to login anyway, we ensure person has a
user id when validating a login
2 jobs for <span class="ref-name">fix/more_setId_fixes</span>
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-TestRunner2

00:42:42

running ERP5.UnitTest-TestRunner2

8202:21:56