cannon: add newline to hello world

cannon/example/hello/main.go

@@ -3,5 +3,5 @@ package main
 import "os"
 
 func main() {
-	_, _ = os.Stdout.Write([]byte("hello world!"))
+	_, _ = os.Stdout.Write([]byte("hello world!\n"))
 }

cannon/mipsevm/evm_test.go

@@ -184,7 +184,7 @@ func TestHelloEVM(t *testing.T) {
 	require.True(t, state.Exited, "must complete program")
 	require.Equal(t, uint8(0), state.ExitCode, "exit with 0")
 
-	require.Equal(t, "hello world!", stdOutBuf.String(), "stdout says hello")
+	require.Equal(t, "hello world!\n", stdOutBuf.String(), "stdout says hello")
 	require.Equal(t, "", stdErrBuf.String(), "stderr silent")
 }
 

cannon/mipsevm/state_test.go

@@ -93,7 +93,7 @@ func TestHello(t *testing.T) {
 	require.True(t, state.Exited, "must complete program")
 	require.Equal(t, uint8(0), state.ExitCode, "exit with 0")
 
-	require.Equal(t, "hello world!", stdOutBuf.String(), "stdout says hello")
+	require.Equal(t, "hello world!\n", stdOutBuf.String(), "stdout says hello")
 	require.Equal(t, "", stdErrBuf.String(), "stderr silent")
 }