Update git submodules

* Update helpcontent2 from branch 'master'
  - fix icon size
    
    Change-Id: I9550ef8ccf4d10ad393ed615573ab9893632f371
    Reviewed-on: https://gerrit.libreoffice.org/73305
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 9a0f4fb1

-Subproject commit 3e4a49f5e61c535044538a23eaf7a6b222a7c57a
+Subproject commit 9a0f4fb18ab7832dbafb4b789279411f5aa8cecd