fdo#81264 Calc is not accessible to screen readers if sheet is modified [a11y]

When the IA2 changes was merged it removed the call to CommitFocusGained
and thereby stopped sending a STATE_CHANGED FOCUSED. A big thank you to
Joanmarie Diggs for noticing the lack of that event.

I only tested the patch on Fedora, but I will have a look at Windows with
NVDA as soon as the patch gets included in the daily builds.

Change-Id: Ic616d1b367ad8b8ed5d243e0ba124764082e96f1
Reviewed-on: https://gerrit.libreoffice.org/11451Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Eike Rathke <erack@redhat.com>

sc/source/ui/Accessibility/AccessibleSpreadsheet.cxx

@@ -362,6 +362,7 @@ void ScAccessibleSpreadsheet::LostFocus()
 
 void ScAccessibleSpreadsheet::GotFocus()
 {
+    CommitFocusGained();
     AccessibleEventObject aEvent;
     aEvent.EventId = AccessibleEventId::ACTIVE_DESCENDANT_CHANGED;
     aEvent.Source = uno::Reference< XAccessibleContext >(this);