manifest: don't set the ostree remote from the source in the pipeline

When we want the source URL to be set as the remote for the system, we
define it at the distro level.  In the pipeline, if no remote URL is
set, don't add a remote stage at all.

pkg/manifest/ostree_deployment.go

@@ -173,24 +173,21 @@ func (p *OSTreeDeployment) serialize() osbuild.Pipeline {
 		},
 	))
 
-	remoteURL := p.Remote.URL
-	if remoteURL == "" {
-		// if the remote URL for the image is not specified, use the source commit URL
-		remoteURL = commit.URL
-	}
-	pipeline.AddStage(osbuild.NewOSTreeRemotesStage(
-		&osbuild.OSTreeRemotesStageOptions{
-			Repo: "/ostree/repo",
-			Remotes: []osbuild.OSTreeRemote{
-				{
-					Name:        p.Remote.Name,
-					URL:         remoteURL,
-					ContentURL:  p.Remote.ContentURL,
-					GPGKeyPaths: p.Remote.GPGKeyPaths,
+	if p.Remote.URL != "" {
+		pipeline.AddStage(osbuild.NewOSTreeRemotesStage(
+			&osbuild.OSTreeRemotesStageOptions{
+				Repo: "/ostree/repo",
+				Remotes: []osbuild.OSTreeRemote{
+					{
+						Name:        p.Remote.Name,
+						URL:         p.Remote.URL,
+						ContentURL:  p.Remote.ContentURL,
+						GPGKeyPaths: p.Remote.GPGKeyPaths,
+					},
 				},
 			},
-		},
-	))
+		))
+	}
 
 	pipeline.AddStage(osbuild.NewOSTreeFillvarStage(
 		&osbuild.OSTreeFillvarStageOptions{