test: Don't leak file descriptor

Signed-off-by: Radostin Stoyanov <rstoyanov1@gmail.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

test/inhfd/fifo.py

@@ -14,7 +14,7 @@ def create_fds():
 	os.rmdir(tdir)
 
 	mnt_id = -1;
-	f = open("/proc/self/fdinfo/%d" % fd1.fileno())
+	with open("/proc/self/fdinfo/%d" % fd1.fileno()) as f:
 		for l in f:
 			l = l.split()
 			if l[0] == "mnt_id:":