ci: stop testing Linux 32-bit builds

ci: stop testing Linux 32-bit builds

The GitHub Actions image has had a longstanding problem with the
dependencies required for 32-bit builds. The current work around no
longer fixes the issue. Stop testing 32-bit builds to avoid false
positive failures with our CI testing.

We can re-enable 32-bit builds when this issue is fixed upstream.

Details: https://github.com/actions/runner-images/issues/4589

Signed-off-by: Vincent Fu <vincent.fu@samsung.com>