testHalJsonStyle: fix _makeDocument with hash randomization.

With PYTHONHASHSEED=0, editing a document like this:

    foo.edit(
      title="live_test_%s" % new_id,
      reference="live_test_%s" % new_id
    )

only sets the reference, because it sets the reference first and then
when setting title it already has the "live_test_%s" % new_id value (
because title is acquired from reference).

With PYTHONHASHSEED set, the order is not guaranteed and sometimes
title is edited before reference. This is revealed by
testHalJsonStyle.TestERP5Document_getHateoas_mode_search with
PYTHONHASHSEED 465.

bt5/erp5_hal_json_style/TestTemplateItem/portal_components/test.erp5.testHalJsonStyle.py

@@ -174,12 +174,9 @@ class ERP5HALJSONStyleSkinsMixin(ERP5TypeTestCase):
 
   def _makeDocument(self):
     new_id = self.generateNewId()
-    foo = self.portal.foo_module.newContent(portal_type="Foo")
-    foo.edit(
-      title="live_test_%s" % new_id,
-      reference="live_test_%s" % new_id
-    )
-    return foo
+    return self.portal.foo_module.newContent(
+      portal_type="Foo",
+      reference="live_test_%s" % new_id)
 
 
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