Bug 29158: (bug 22435 follow-up) Remove ref to account_offset_types.sql in intaller

Bug 29158: (bug 22435 follow-up) Remove ref to account_offset_types.sql in intaller

Caused by
  commit 3d6a6e79f79bfbc17807072faf0ff1d4e6aafb82
  Bug 22435: (follow-up) Drop account_offset_types table
that removes the file but the reference to it from the installer
process.

Test plan:
Go through the install process and notice that the following warning
does not appear in the log:
[2021/10/25 09:47:58] [WARN] Something went wrong loading file /kohadevbox/koha/installer/data/mysql/mandatory/account_offset_types.sql (Couldn't read '/kohadevbox/koha/installer/data/mysql/mandatory/account_offset_types.sql' : No such file or directory at /usr/share/perl5/DBIx/RunSQL.pm line 180.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>