test: net: coap: update tests
test: net: coap: update tests

Update test to ensure that any file can be tranfered,
not only files that are aligned with the packet size.

Signed-off-by: Efrain Calderon <a766981570b342e88f5fe6435336df8d135300f0@aquarobur.com>
Signed-off-by: Robert Lubos <9d28997c6894a2d0321a7bb399169af7ce99b64e@nordicsemi.no>

galak/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr