fix: serply credential check query might return empty records (#12784)

api/core/tools/provider/builtin/websearch/tools/job_search.py

     def parse_results(res: dict) -> str:
         """Process response from Serply Job Search."""
         jobs = res.get("jobs", [])
-        if not jobs:
+        if not res or "jobs" not in res:
             raise ValueError(f"Got error from Serply: {res}")
 
         string = []

api/core/tools/provider/builtin/websearch/tools/news_search.py

     def parse_results(res: dict) -> str:
         """Process response from Serply News Search."""
         news = res.get("entries", [])
-        if not news:
+        if not res or "entries" not in res:
             raise ValueError(f"Got error from Serply: {res}")
 
         string = []

api/core/tools/provider/builtin/websearch/tools/scholar_search.py

     def parse_results(res: dict) -> str:
         """Process response from Serply News Search."""
         articles = res.get("articles", [])
-        if not articles:
+        if not res or "articles" not in res:
             raise ValueError(f"Got error from Serply: {res}")
 
         string = []

api/core/tools/provider/builtin/websearch/tools/web_search.py

     def parse_results(res: dict) -> str:
         """Process response from Serply Web Search."""
         results = res.get("results", [])
-        if not results:
+        if not res or "results" not in res:
             raise ValueError(f"Got error from Serply: {res}")
 
         string = []