add dnf download plugin

Author: bmastbergen

.github/workflows/build-check_x86_64.yml

@@ -23,6 +23,7 @@ jobs:
           dnf install --enablerepo=crb bc dwarves kernel-devel openssl-devel elfutils-libelf-devel -y
       - name: Get kernel src rpm
         run: |
+          dnf install 'dnf-command(download)'
           dnf download --source kernel
           ls *.src.rpm
       - name: Checkout code