better handle example file at any depth

packages/node_modules/@node-red/registry/lib/library.js

@@ -51,9 +51,6 @@ function getFlowsFromPath(path) {
                     }
                     i++;
                 })
-                if (!result.hasOwnProperty("f")) {
-                    reject(result);
-                }
                 resolve(result);
             })
         });
@@ -63,9 +60,10 @@ function getFlowsFromPath(path) {
 function addNodeExamplesDir(module,path) {
     exampleRoots[module] = path;
     return getFlowsFromPath(path).then(function(result) {
+        if (JSON.stringify(result).indexOf('{"f":') === -1) { return; }
         exampleFlows = exampleFlows||{};
         exampleFlows[module] = result;
-    }, function() { return; });
+    });
 }
 function removeNodeExamplesDir(module) {
     delete exampleRoots[module];