Handle "no links found" properly

[PROger4ever]

Problem

When no links found in incoming message, ytdlbot tries to send an empty message:

[2024-09-24 01:01:01 ytdl_bot.py:589 I] start ['Respect💯 Greatest Save🦸\u200d♂️ #shorts #short #status #humanity #viral\nhttps://youtube.com/shorts/1K1pMdQzV1M?si=uze3jaacXuKeWDNG']
[2024-09-24 01:01:01 database.py:113 I] Setting metrics: bad_request
[2024-09-24 01:01:01 _client.py:1038 I] HTTP Request: POST https://www.youtube.com/youtubei/v1/search?key=GOOGLE_API_KEY_HIDDEN "HTTP/1.1 200 OK"
[2024-09-24 01:01:01 dispatcher.py:328 E] Telegram says: [400 MESSAGE_EMPTY] - The message sent is empty or contains invalid characters (caused by "messages.SendMessage")
Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/pyrogram/dispatcher.py", line 317, in handler_worker
    await self.loop.run_in_executor(
  File "/usr/local/lib/python3.11/concurrent/futures/thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/ytdlbot/ytdlbot/ytdl_bot.py", line 118, in wrapper
    return func(client, message)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/ytdlbot/ytdlbot/ytdl_bot.py", line 596, in download_handler
    message.reply_text(text, quote=True, disable_web_page_preview=True)
  File "/usr/local/lib/python3.11/site-packages/pyrogram/sync.py", line 78, in async_to_sync_wrap
    return asyncio.run_coroutine_threadsafe(coroutine, main_loop).result()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/concurrent/futures/_base.py", line 456, in result
    return self.__get_result()
           ^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/concurrent/futures/_base.py", line 401, in __get_result
    raise self._exception
  File "/usr/local/lib/python3.11/site-packages/pyrogram/types/messages_and_media/message.py", line 1377, in reply_text
    return await self._client.send_message(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pyrogram/methods/messages/send_message.py", line 168, in send_message
    r = await self.invoke(
        ^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pyrogram/methods/advanced/invoke.py", line 94, in invoke
    r = await session.invoke(
        ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pyrogram/session/session.py", line 406, in invoke
    return await self.send(query, timeout=timeout)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/pyrogram/session/session.py", line 374, in send
    RPCError.raise_it(result, type(data))
  File "/usr/local/lib/python3.11/site-packages/pyrogram/errors/rpc_error.py", line 91, in raise_it
    raise getattr(
pyrogram.errors.exceptions.bad_request_400.MessageEmpty: Telegram says: [400 MESSAGE_EMPTY] - The message sent is empty or contains invalid characters (caused by "messages.SendMessage")

So user doesn't understand what's going on :)