Be sure to update UUID when placing new elements

Fixes https://gitlab.com/kicad/code/kicad/issues/12588

(cherry picked from commit a5da46459c)

eeschema/tools/sch_drawing_tools.cpp

@@ -750,6 +750,7 @@ int SCH_DRAWING_TOOLS::SingleClickPlace( const TOOL_EVENT& aEvent )
                 }
 
                 SCH_ITEM* newItem = static_cast<SCH_ITEM*>( previewItem->Clone() );
+                const_cast<KIID&>( newItem->m_Uuid ) = KIID();
                 newItem->SetPosition( cursorPos );
                 newItem->SetFlags( IS_NEW );