component/tesseract: Workaround for slaprunner paths with double slashs

This is basically the same problem as in 1b291415
(component/ghostscript: Workaround for slaprunner paths with double
slashs, 2021-06-02)
Status Job ID Name Coverage
  External
running ERP5.UnitTest-TesseractDoubleSlash

28741:27:52

running SlapOS.Eggs.UnitTest-Master.Python2

28741:26:33

running SlapOS.Eggs.UnitTest-Master.Python3

28741:26:43

running SlapOS.SlapRunner.ResilienceTest-Master

28741:26:39

running SlapOS.SlapRunner.ResilienceTest-Master.ERP5

28741:27:29