ci: Disable AArch64 Linux SDK build

This commit temporarily disables AArch64 Linux Zephyr SDK build because
the AArch64 CI runner AWS spot instances are too frequently shut down
and unable to complete the full build cycle.

Re-enable this when the self-hosted zephyr-runner v2 is deployed and
available for production use.

Signed-off-by: Stephanos Ioannidis <[email protected]>

Author: stephanosio

.github/workflows/ci.yml

@@ -187,7 +187,7 @@ jobs:
 
         if [ "${build_host_all}" == "y" ]; then
           build_host_linux_x86_64="y"
-          build_host_linux_aarch64="y"
+          # build_host_linux_aarch64="y"
           build_host_macos_x86_64="y"
           build_host_macos_aarch64="y"
           build_host_windows_x86_64="y"