pytest: fix old code in test, which can cause spurious failures.

We generated blocks to announce the channel, but it can also expire
the HTLC if the timing is wrong.  We don't need to anyway, since we
fixed the FIXME; we store local unannounced channels for restoration

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

tests/test_pay.py

@@ -278,8 +278,6 @@ def test_payment_success_persistence(node_factory, bitcoind, executor):
     assert len(payments) == 1 and payments[0]['status'] == 'complete'
     assert len(invoices) == 1 and invoices[0]['status'] == 'paid'
 
-    # FIXME: We should re-add pre-announced routes on startup!
-    bitcoind.generate_block(5)
     l1.wait_channel_active(chanid)
 
     # A duplicate should succeed immediately (nop) and return correct preimage.