Update git submodules

* Update helpcontent2 from branch 'master'
  - tdf#53524 help-submodule - grid control Dialog editor
    
    Change-Id: Ie6918fdc9eb0cfed7042362cb1ad223e908d6d8a
    Reviewed-on: https://gerrit.libreoffice.org/68895
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 8b9d37bf

-Subproject commit eb2972e06b1ac3210f1de1a6e9ade2d049aaf976
+Subproject commit 8b9d37bf1bb9bfc21343cbd02f21201c56cf05ca