tests: fix disabling of GPIO interrupt issue

According to ZEP-1717, removing the callback from
the gpio is not enough to disable interruptions.
You also need to call gpio_pin_configure() on
the input pin without the GPIO_INT flag to totally
disable the interrupt for the pin.

This commit will stop level interrupt from being
fired constantly.

Change-Id: I019d7cea0bc0d5e5ff4b74165472ed11de1733bb
Signed-off-by: Qiu Peiyang <peiyangx.qiu@intel.com>