Update git submodules

* Update helpcontent2 from branch 'master'
  - tdf#115254 Some branch bookmarks are'nt working 29
    
    Module extensions, scanner + spropctrl
    
    Change-Id: I3984f52dd383e3d9153312418964af513408640b
    Reviewed-on: https://gerrit.libreoffice.org/60515
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 847b17c7

-Subproject commit 4890637bf3ce3cebead1b1bb5395ada90cb2673a
+Subproject commit 847b17c70c53740bba9980fa8d72b71554d5925d