itest: remove unnecessary channel close and node shutdown

Since we don't have standby nodes anymore, we don't need to close the
channels when the test finishes. Previously we would do so to make sure
the standby nodes have a clean state for the next test case, which is no
longer relevant.

itest/lnd_psbt_test.go

@@ -324,13 +324,6 @@ func runPsbtChanFunding(ht *lntest.HarnessTest, carol, dave *node.HarnessNode,
 	}
 	resp := dave.RPC.AddInvoice(invoice)
 	ht.CompletePaymentRequests(carol, []string{resp.PaymentRequest})
-
-	// To conclude, we'll close the newly created channel between Carol and
-	// Dave. This function will also block until the channel is closed and
-	// will additionally assert the relevant channel closing post
-	// conditions.
-	ht.CloseChannel(carol, chanPoint)
-	ht.CloseChannel(carol, chanPoint2)
 }
 
 // runPsbtChanFundingExternal makes sure a channel can be opened between carol
@@ -499,13 +492,6 @@ func runPsbtChanFundingExternal(ht *lntest.HarnessTest, carol,
 	}
 	resp := dave.RPC.AddInvoice(invoice)
 	ht.CompletePaymentRequests(carol, []string{resp.PaymentRequest})
-
-	// To conclude, we'll close the newly created channel between Carol and
-	// Dave. This function will also block until the channels are closed and
-	// will additionally assert the relevant channel closing post
-	// conditions.
-	ht.CloseChannel(carol, chanPoint)
-	ht.CloseChannel(carol, chanPoint2)
 }
 
 // runPsbtChanFundingSingleStep checks whether PSBT funding works also when
@@ -649,12 +635,6 @@ func runPsbtChanFundingSingleStep(ht *lntest.HarnessTest, carol,
 	}
 	resp := dave.RPC.AddInvoice(invoice)
 	ht.CompletePaymentRequests(carol, []string{resp.PaymentRequest})
-
-	// To conclude, we'll close the newly created channel between Carol and
-	// Dave. This function will also block until the channel is closed and
-	// will additionally assert the relevant channel closing post
-	// conditions.
-	ht.CloseChannel(carol, chanPoint)
 }
 
 // testSignPsbt tests that the SignPsbt RPC works correctly.