update GPT4 endpoint

app.py

@@ -241,7 +241,7 @@ async def start_playwright(question: str):
     page = await browser.new_page()
     
     # note all methods are async (use the "await" keyword)
-    await page.goto("https://basicchatbot.azurewebsites.net/")
+    await page.goto(os.environ["Endpoint_GPT4"])
     # print("Title of Web: ", await page.title())
     end_t = time.time()
     print("New Page Done:",  end_t - start_t)