software.cfg: update slapos to 1.0.244

We have a test suite OfficeJS.Appstore.UnitTest-Master failing to run since a few days with an error like this:

 $ /srv/slapgrid/slappart3/t/cag/i/5/bin/runTestSuite --help
 Traceback (most recent call last):
   File "../bin/runTestSuite", line 298, in <module>
     import Products.ERP5Type.tests.runTestSuite
   File "../parts/erp5/product/ERP5Type/__init__.py", line 86, in <module>
     from Products.ERP5Type.Utils import initializeProduct, updateGlobals
   File "../parts/erp5/product/ERP5Type/Utils.py", line 32, in <module>
     from past.builtins import cmp
 ImportError: No module named past.builtins

This is because with erp5 commit a17bb91030 (py2/py3: Make Products code compatible with both python2 and python3., 2022-04-13) we have a new dependency. That dependency is provided by the new SlapOS software release, so ERP5 has a minimal requirement for this new SlapOS software release.

These changes are about updating SlapOS software release. The old version pins are no longer needed here, because SlapOS software release provides them. SlapOS now comes with a newer version of Zope2 and also with their own patches to Zope2, so we use += to apply this patch on top of SlapOS patches