Don't include shape/object name when exporting to tagged PDF

most of the time shapes have generated names such as 'Shape 42', those
have ~no added value so let's not include them in Alt text

Change-Id: I30314d5e901e11722e609dbf7ceddf74c5ed9707
Reviewed-on: https://gerrit.libreoffice.org/68520
Tested-by: Jenkins
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

drawinglayer/source/processor2d/vclmetafileprocessor2d.cxx

@@ -1006,15 +1006,10 @@ namespace drawinglayer
                 // for PDF export
                 if(mpPDFExtOutDevData->GetIsExportTaggedPDF() && nullptr != getObjectInfoPrimitive2D())
                 {
-                    OUString aAlternateDescription(getObjectInfoPrimitive2D()->getName());
+                    OUString aAlternateDescription;
 
                     if(!getObjectInfoPrimitive2D()->getTitle().isEmpty())
                     {
-                        if(!aAlternateDescription.isEmpty())
-                        {
-                            aAlternateDescription += " - ";
-                        }
-
                         aAlternateDescription += getObjectInfoPrimitive2D()->getTitle();
                     }