Fix qemu/test_qemu.py when run in github action (CI)

The qemu/test_qemu.py test has been disabled (renamed _test_qemu.py) b/c the fetching of images from the iptfs-dev repository is failing for odd reasons. The auth token was updated in the FETCH_GH_TOKEN secret, but the test is still failing.

Rename _test_qemu.py back to test_qemu.py on a branch and debug.