fix: report correct error when task doesn't exist (knative#1915)

Signed-off-by: Matej Vasek <mvasek@redhat.com>

pkg/pipelines/tekton/templates.go

@@ -284,10 +284,14 @@ func deleteAllPipelineTemplates(f fn.Function) string {
 }
 
 func getTaskSpec(taskUrlTemplate string) (string, error) {
-	resp, err := http.Get(fmt.Sprintf(taskUrlTemplate, FuncRepoRef, FuncRepoBranchRef))
+	u := fmt.Sprintf(taskUrlTemplate, FuncRepoRef, FuncRepoBranchRef)
+	resp, err := http.Get(u)
 	if err != nil {
 		return "", err
 	}
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("cannot get task: %q bad http code: %d", u, resp.StatusCode)
+	}
 	defer resp.Body.Close()
 	var data map[string]any
 	dec := yaml.NewDecoder(resp.Body)