Update git submodules

* Update helpcontent2 from branch 'master'
  - fix forgotten LANG->LANGUAGE
    
    Change-Id: Idcfd73213452510f769854062d0916a3c871b548
    Reviewed-on: https://gerrit.libreoffice.org/70982
    Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
    

helpcontent2 @ 5c561c2f

-Subproject commit 8a21dc1cc51f0363b33e59b5c34c74d5c6737f1e
+Subproject commit 5c561c2f3744c5697ea6d25357f4223f0dbe977e