Fix detection of invalid SQL generated id (smaller than what is stored in ZODB)

Another fix would be to modify
SQLNonContinuousIncreasingIdGenerator._generateNewId
so that ZODB last id is read before we generate a new one,
but '_p_independent' is deprecated anyway
(and already removed in newest versions of ZODB).

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@41229 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/Utils.py

@@ -3182,11 +3182,6 @@ class ScalarMaxConflictResolver(persistent.Persistent):
   def _p_resolveConflict(self, old, first_id, second_id):
     return max(first_id, second_id)
 
-  def _p_independent(self):
-    # My state doesn't depend on or materially effect the state of
-    # other objects.
-    return 1
-
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