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

30734:10:24

running SlapOS.Eggs.UnitTest-Master.Python2

30734:09:05

running SlapOS.Eggs.UnitTest-Master.Python3

30734:09:16

running SlapOS.SlapRunner.ResilienceTest-Master

30734:09:11

running SlapOS.SlapRunner.ResilienceTest-Master.ERP5

30734:10:02