ci: stop passing ci-repository to kmod-ci

The CI has deprecated ci-repository and ci-ref since those can be
inferred from the "uses:" tag.

Remove the deprecated input from the workflow.

Signed-off-by: Ralf Lici <ralf@mandelbit.com>

Author: ralflici

.github/workflows/vng-selftests.yml

@@ -13,7 +13,6 @@ jobs:
   vng-selftests:
     uses: mandelbitdev/kmod-ci/.github/workflows/out-of-tree-vng.yml@main
     with:
-      ci-repository: mandelbitdev/kmod-ci
       cache-prefix: ovpn-backports
       guest-script: ci/run-selftests.sh
       prepare-command: ./backports-ctl.sh get-ovpn -t