Update git submodules

* Update helpcontent2 from branch 'master'
  - tdf#122631 Describe Shift+F5 in Writer
    
    Change-Id: I2191fa502c0db26854c10cff4a6e5f2b094a8557
    Reviewed-on: https://gerrit.libreoffice.org/66087
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 3c489aa0

-Subproject commit e2d3ddaae1d9542b2060275b44bc48eef1bb0991
+Subproject commit 3c489aa0b0f2108d1f7bd69a94431921797eedf3