added tests

tests/test_loading.py

@@ -0,0 +1,8 @@
+from langflow import load_flow_from_json
+import os
+
+def test_loading():
+    for json_file in os.listdir('./examples'):
+        if json_file.endswith('.json'):
+            flow = load_flow_from_json(f'./examples/{json_file}', build=False)
+            assert flow is not None