fix checkout.py typo
fix checkout.py typo

Change-Id: I74ccd3bb7322d098cd8e7dd8be38dcb187575e1f
Reviewed-on: http://gerrit.aldebaran.lan/46301
Tested-by: gerrit
Reviewed-by: dmerejkowsky <1e4b13000fa8777df4cefd2fd8215187e3deb062@aldebaran-robotics.com>

dmerejkowsky/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild