Fix missing edge from toTopoGeom return (#1968)

git-svn-id: http://svn.osgeo.org/postgis/trunk@11152 b70326c6-7e19-0410-871a-916f4a2858ee
Improve the test for #1968 to also check duplicated components

git-svn-id: http://svn.osgeo.org/postgis/trunk@11155 b70326c6-7e19-0410-871a-916f4a2858ee