erp5_open_trade: Don't archive already archived Open Orders

See merge request !1766
9 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

01:03:55

passed ERP5.PerformanceTest-Master

00:26:53

passed ERP5.UnitTest-Master

01:26:23

failed ERP5.UnitTest-Zope2

04:19:36

passed SlapOS.Eggs.UnitTest-Master.Python2

00:13:06

passed SlapOS.Eggs.UnitTest-Master.Python3

00:14:59

passed Wendelin.UnitTest-Master

00:40:08

passed SlapOS.Eggs.UnitTest-Master.Python2

00:12:50

passed SlapOS.Eggs.UnitTest-Master.Python3

00:14:05