Fix: add image2text issue. (#5431)

### What problem does this PR solve?

#5356

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

api/apps/llm_app.py

@@ -264,7 +264,7 @@ def add_llm():
         try:
             with open(os.path.join(get_project_base_directory(), "web/src/assets/yay.jpg"), "rb") as f:
                 m, tc = mdl.describe(f.read())
-                if not tc:
+                if not m and not tc:
                     raise Exception(m)
         except Exception as e:
             msg += f"\nFail to access model({mdl_nm})." + str(e)