samples: net: updatehub: Add sample.yaml file
samples: net: updatehub: Add sample.yaml file

Add missing sample.yaml file to enable CI build tests. Local tests can
be executed executing sanitycheck:

./scripts/sanitycheck -l --testcase-root samples/net/updatehub

Signed-off-by: Gerson Fernando Budke <de7eb9f159f7e30f8dcdecee89db6e1a285bf5b2@ossystems.com.br>

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