patches: Fix sqlvar monkey patch bug for Zope2.

<dtml-sqlvar "None" type=string> should be 'null', not 'None'.
25 jobs for master in 0 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  External
failed ERP5.CodingStyleTest-Master

00:48:19

passed ERP5.PerformanceTest-Master

00:26:46

failed ERP5.UnitTest-Master

01:24:18

failed ERP5.UnitTest-Zope2

01:51:22

passed SlapOS.Eggs.UnitTest-Master.Python2

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passed SlapOS.Eggs.UnitTest-Master.Python3

00:17:02

passed Wendelin.UnitTest-Master

00:38:45

failed ERP5.CodingStyleTest-Master

00:38:47

failed ERP5.CodingStyleTest-Master

00:54:14

passed ERP5.PerformanceTest-Master

00:26:45

passed ERP5.PerformanceTest-Master

00:26:43

failed ERP5.UnitTest-Master

01:45:15

failed ERP5.UnitTest-Master

01:12:52

failed ERP5.UnitTest-Zope2

01:31:12

failed ERP5.UnitTest-Zope2

02:25:02

passed SlapOS.Eggs.UnitTest-Master.Python2

00:16:26

passed SlapOS.Eggs.UnitTest-Master.Python2

00:20:12

passed SlapOS.Eggs.UnitTest-Master.Python2

00:23:37

passed SlapOS.Eggs.UnitTest-Master.Python2

00:17:34

passed SlapOS.Eggs.UnitTest-Master.Python3

00:18:38

passed SlapOS.Eggs.UnitTest-Master.Python3

00:31:14

passed SlapOS.Eggs.UnitTest-Master.Python3

00:35:30

passed SlapOS.Eggs.UnitTest-Master.Python3

00:25:44

passed Wendelin.UnitTest-Master

00:21:49

failed Wendelin.UnitTest-Master

00:31:47