Delay destroy of unlinked instances if modification_date is recent

master/bt5/slapos_cloud/SkinTemplateItem/portal_skins/slapos_cloud/SoftwareInstance_tryToGarbageUnlinkedInstance.py

 from zExceptions import Unauthorized
+from DateTime import DateTime
+from Products.ERP5Type.DateUtils import addToDate
 if REQUEST is not None:
   raise Unauthorized
 
@@ -12,6 +14,11 @@ if hosting_subscription is None or \
     hosting_subscription.getSlapState() == "destroy_requested":
   return
 
+# If instance modificationDate is too recent, skip
+# Delay destroy of unlinked instances
+if instance.getModificationDate() - addToDate(DateTime(), {'minute': -50}) > 0:
+  return
+
 if instance.getPredecessorRelatedValue() is None:
   # This unlinked instance to parent should be removed
   is_slave = False