ci: re-enable uefi secure boot

Kernel 6.11.0-1018-azure is now in use, which has a workaround
for the HyperV bug, so this should work again in GHA

.github/workflows/coverage.yml

@@ -50,9 +50,6 @@ jobs:
 
       - name: Configure
         run: |
-          # XXX: drop after the HyperV bug that breaks secure boot KVM guests is solved
-          sed -i "s/'firmware'\s*:\s*'auto'/'firmware' : 'uefi'/g" test/*/meson.build
-
           tee mkosi/mkosi.local.conf <<EOF
           [Distribution]
           Distribution=arch