Update git submodules

* Update helpcontent2 from branch 'master'
  - Related: tdf#121134: Changing http to https where possible
    
    Change-Id: I5b7df43fd43c07377ac2ec1e0dcecb7a245330f9
    Reviewed-on: https://gerrit.libreoffice.org/63011
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 319ad0a3

-Subproject commit 3a506373636d8c224dab844b4248a338d7a2e696
+Subproject commit 319ad0a302758e11d021145ac5e74cb79d849203