qvm-template-repo-query: don't set pluginpath for DNF5

Setting pluginpath makes DNF5 look for plugin configs for every
installed libdnf plugin. If any is missing, it fails to start.
Since the downloadurl plugin isn't applicable to DNF5 don't set
alternative pluginpath to avoid the problem of missing configs for other
plugins.

QubesOS/qubes-issues#9244

qubes-rpc/qvm-template-repo-query

@@ -26,11 +26,18 @@ repodir=$(mktemp -d)
 trap 'rm -r "$repodir"' EXIT
 cat > "$repodir/template.repo"
 
+DNF5=false
+if [ "$(readlink /usr/bin/dnf)" = "dnf5" ]; then
+    DNF5=true
+fi
+
 OPTS+=(-y "--setopt=reposdir=${repodir}" --quiet)
 
-# use vendored 'downloadurl' dnf-plugin (fork of 'download' plugin), to print
-# all mirrors
-OPTS+=("--setopt=pluginpath=/usr/lib/qubes/dnf-plugins")
+if ! $DNF5; then
+    # use vendored 'downloadurl' dnf-plugin (fork of 'download' plugin), to print
+    # all mirrors
+    OPTS+=("--setopt=pluginpath=/usr/lib/qubes/dnf-plugins")
+fi
 
 if ! command -v dnf >/dev/null; then
     echo "ERROR: dnf command is missing, please use newer template for your UpdateVM to download templates." >&2