Update git submodules

* Update helpcontent2 from branch 'master'
  - tdf#119415 Add placeholder text for index filter
    
    Change-Id: If7a0a863eb6b8bb95a5b6236f4f3d490739810a1
    Reviewed-on: https://gerrit.libreoffice.org/63672
    Tested-by: Jenkins
Reviewed-by: Ilmari Lauhakangas <ilmari.lauhakangas@libreoffice.org>
Reviewed-by: Adolfo Jayme Barrientos <fitojb@ubuntu.com>
    

helpcontent2 @ 126ef50e

-Subproject commit 789b9f58490c731c2497152be787130851977967
+Subproject commit 126ef50e9756e79bf5b500edeaa9275260a1b7d3