Update git submodules

* Update helpcontent2 from branch 'master'
  - More detailed help of Calc's Sheet > Link to external data
    
    Make it more clear there has to be at least 1 named range in
    Excel of Calc documents
    
    Change-Id: I782c4d2c10ee52320bfdf147652883f5e7b4751a
    Reviewed-on: https://gerrit.libreoffice.org/72076
    Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
    

helpcontent2 @ 8ba1c197

-Subproject commit 2f8fbb8c0aa867e8986a496820cf79d75a5d5ea1
+Subproject commit 8ba1c1976c652b804a02267a8035606b10db2682