Fix fd leak of shim log

Open shim v2 log with the flag `O_RDWR` will cause the `Read()` block
forever even if the pipe has been closed on the shim side. Then the
`io.Copy()` would never return and lead to a fd leak.
Fix typo when closing shim v1 log which causes the `stdouLog` leak.
Update `numPipes` function in test case to get the opened FIFO
correctly.

Signed-off-by: Li Yuxuan <liyuxuan04@baidu.com>

runtime/v1/shim/client/client.go

@@ -98,9 +98,9 @@ func WithStart(binary, address, daemonAddress, cgroup string, debug bool, exitHa
 			cmd.Wait()
 			exitHandler()
 			if stdoutLog != nil {
-				stderrLog.Close()
+				stdoutLog.Close()
 			}
-			if stdoutLog != nil {
+			if stderrLog != nil {
 				stderrLog.Close()
 			}
 		}()