fix: Ensure skip_if_unavailable=True during RPM package metadata refresh (dnf/tdnf)

Author: vinceaperri

toolkit/tools/pkg/imagecustomizerlib/customizepackages_rpm.go

@@ -275,7 +275,15 @@ func refreshRpmPackageMetadata(ctx context.Context, imageChroot *safechroot.Chro
 	_, span := startRefreshPackageMetadataSpan(ctx)
 	defer span.End()
 
-	args := []string{pmHandler.getVerbosityOption(), "check-update", "--refresh", "--assumeyes"}
+	// --setopt=skip_if_unavailable=False ensures failures to fetch repo metadata are fatal. TDNF already does this by
+	// default, but DNF on some distros (e.g. Azure Linux 4.0) defaults to skip_if_unavailable=True, so we set it
+	// explicitly for both. It's important to ensure repo metadata is refreshed successfully to ensure correct package
+	// versions are installed as intended by the user's repo configuration. It also has the benefit of failing slightly
+	// faster when repos are misconfigured.
+	args := []string{
+		pmHandler.getVerbosityOption(), "check-update", "--refresh", "--assumeyes",
+		"--setopt=skip_if_unavailable=False",
+	}
 
 	args = append(args, "--setopt=reposdir="+rpmsMountParentDirInChroot)