itest: remove old CPFP tests

The old commitment deadline is removed as it's no longer relevant.

itest/list_on_test.go

@@ -205,10 +205,6 @@ var allTestCases = []*lntest.TestCase{
 		Name:     "channel unsettled balance",
 		TestFunc: testChannelUnsettledBalance,
 	},
-	{
-		Name:     "commitment deadline",
-		TestFunc: testCommitmentTransactionDeadline,
-	},
 	{
 		Name:     "channel force closure",
 		TestFunc: testChannelForceClosure,