funding+lnwire: rename FundingLocked related tests

This commit is created by running the following commands,

```shell
gofmt -d -w -r 'fundingLockedAlice -> channelReadyAlice' .
gofmt -d -w -r 'fundingLockedBob -> channelReadyBob' .
gofmt -d -w -r 'assertHandleFundingLocked -> assertHandleChannelReady' .
gofmt -d -w -r 'assertFundingLockedSent -> assertChannelReadySent' .
gofmt -d -w -r 'aliceFundingLocked -> aliceChannelReady' .
gofmt -d -w -r 'bobFundingLocked -> bobChannelReady' .
gofmt -d -w -r 'FuzzFundingLocked -> FuzzChannelReady' .
gofmt -d -w -r 'newMsgFundingLocked -> newMsgChannelReady' .
gofmt -d -w -r 'TestFundingManagerReceiveFundingLockedTwice -> TestFundingManagerReceiveChannelReadyTwice' .
gofmt -d -w -r 'TestFundingManagerRestartAfterReceivingFundingLocked -> TestFundingManagerRestartAfterReceivingChannelReady' .
```

lnwire/fuzz_test.go

@@ -286,7 +286,7 @@ func FuzzFundingCreated(f *testing.F) {
 	})
 }
 
-func FuzzFundingLocked(f *testing.F) {
+func FuzzChannelReady(f *testing.F) {
 	f.Fuzz(func(t *testing.T, data []byte) {
 		// Prefix with MsgFundingLocked.
 		data = prefixWithMsgType(data, MsgChannelReady)