Update git submodules

* Update helpcontent2 from branch 'master'
  - Related: tdf#121134
    
    Changing internal and external 
    "http://" links to the more secure "https://"
    where https is available,
    even to avoid some redirections.
    
    Cleanup of source file(s) included.
    
    Change-Id: Ica52ea5910bd439fe9cd295c40f7947083b65d6b
    Reviewed-on: https://gerrit.libreoffice.org/62897
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 0846f79c

-Subproject commit 9b58d0269638d2c487349508d7f19dc021fa3a28
+Subproject commit 0846f79c26b9feb6246d3075b4fc49d7b7cdc11f