ci: fix package_core

Author: facchinm

.github/workflows/package_core.yml

@@ -13,7 +13,7 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y --no-install-recommends git cmake wget python3-pip
           wget https://github.com/zephyrproject-rtos/sdk-ng/releases/download/v0.16.8/zephyr-sdk-0.16.8_linux-x86_64_minimal.tar.xz
-          cd zephyr-sdk-0.16.8 && ./setup.sh -t arm-zephyr-eabi -c
+          tar xf zephyr-sdk-0.16.8_linux-x86_64_minimal.tar.xz && cd zephyr-sdk-0.16.8 && ./setup.sh -t arm-zephyr-eabi -c
 
       - name: Initialize
         working-directory: ArduinoCore-zephyr