parallel sweep: remove a test from test_tracepoint.rb that no longer makes sense

Author: luke-gruber

test/-ext-/tracepoint/test_tracepoint.rb

@@ -47,7 +47,6 @@ def test_tracks_objspace_count
     assert_operator stat2[:total_allocated_objects] - stat1[:total_allocated_objects], :>=, newobj_count
     assert_operator 1_000_000, :<=, newobj_count
 
-    assert_operator stat2[:total_freed_objects] + stat2[:heap_final_slots] - stat1[:total_freed_objects], :>=, free_count
     assert_operator stat2[:count] - stat1[:count], :==, gc_start_count
 
     assert_operator gc_start_count, :==, gc_end_mark_count