Address PendingDeprecationWarning from _from_edgelist (#4388)

`__from_edgelist`'s default is causing a `PendingDeprecationWarning` from having a default of `legacy_renum_only=True`.

It appears that this parameter has no effect so it should be OK to change the default so that this warning doesn't appear

Authors:
  - Matthew Roeschke (https://github.com/mroeschke)

Approvers:
  - Rick Ratzel (https://github.com/rlratzel)

URL: #4388

Author: mroeschke

python/cugraph/cugraph/structure/graph_implementation/simpleGraph.py

@@ -131,7 +131,7 @@ def __from_edgelist(
         edge_id=None,
         edge_type=None,
         renumber=True,
-        legacy_renum_only=True,
+        legacy_renum_only=False,
         store_transposed=False,
     ):
         if legacy_renum_only: