github: workflows: Avoid listing tests manually
github: workflows: Avoid listing tests manually

Instead of listing each test manually, use the script itself to list
them:

- When invoking it just exclude the one we don't want by default
- When parsing the output files, use the -l output as a list

Signed-off-by: Carles Cufi <853081dc8dca4fe6a7e3c984752718b5db36e060@nordicsemi.no>

zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr