Update git submodules

* Update helpcontent2 from branch 'master'
  - tdf#118844 Add missing icons in Help pages
    
    Apply strategy #1 described in tdf#118844 comment #3
    
    Change-Id: I072bf837217acc8dc84ff1104324df69e33a22bd
    Reviewed-on: https://gerrit.libreoffice.org/57801
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 6f19b002

-Subproject commit faeb714c09f7420d6ed0c55097de2467e211a13d
+Subproject commit 6f19b002ecde744916b4e7276dd5f35b95f5dab8