correctly pick the seal type based on the network version

Of course, we should really just run all of our tests post actors v2.

node/impl/client/client.go

@@ -159,7 +159,12 @@ func (a *API) ClientStartDeal(ctx context.Context, params *api.StartDealParams)
 		dealStart = ts.Height() + abi.ChainEpoch(dealStartBufferHours*blocksPerHour) // TODO: Get this from storage ask
 	}
 
-	st, err := miner.PreferredSealProofTypeFromWindowPoStType(mi.WindowPoStProofType)
+	networkVersion, err := a.StateNetworkVersion(ctx, types.EmptyTSK)
+	if err != nil {
+		return nil, xerrors.Errorf("failed to get network version: %w", err)
+	}
+
+	st, err := miner.PreferredSealProofTypeFromWindowPoStType(networkVersion, mi.WindowPoStProofType)
 	if err != nil {
 		return nil, xerrors.Errorf("failed to get seal proof type: %w", err)
 	}