tdf#121263 Calc crashes when hide multiple sheets

regression from
	commit 87c06415
    clang-tidy performance-unnecessary-copy-init in sc

Change-Id: I49a7099c0a5e9e684008d2e799f9ee94f867d786
Reviewed-on: https://gerrit.libreoffice.org/63239
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

sc/source/ui/view/viewfun2.cxx

@@ -3045,7 +3045,8 @@ void ScViewFunc::HideTable( const ScMarkData& rMark )
         ScMarkData::MarkedTabsType::const_iterator it;
         std::vector<SCTAB> undoTabs;
 
-        const ScMarkData::MarkedTabsType& selectedTabs = rMark.GetSelectedTabs();
+        // need to take a copy of selectedtabs since it is modified in the loop
+        const ScMarkData::MarkedTabsType selectedTabs = rMark.GetSelectedTabs();
         for (it=selectedTabs.begin(); it!=selectedTabs.end(); ++it)
         {
             nTab = *it;