Update git submodules

* Update helpcontent2 from branch 'master'
  - Fix typo
    
    Change-Id: Ibfbd8efce7c262375e336af242da4fb27a192236
    Reviewed-on: https://gerrit.libreoffice.org/58930
    Tested-by: Jenkins
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>
    

helpcontent2 @ 780b5243

-Subproject commit 9e4660049b5f4c6da3c652f068186e52a360ae3b
+Subproject commit 780b5243abe260f6f37e9c5f6563c58fc2e20818