replace infinite loop with timeout with while loop, when the client is bad

mtprotoproxy.py

@@ -496,9 +496,9 @@ async def handle_handshake(reader, writer):
         writer = CryptoWrappedStreamWriter(writer, encryptor)
         return reader, writer, proto_tag, user, dc_idx, enc_key + enc_iv
 
-    while True:
+    while await reader.read(READ_BUF_SIZE):
         # just consume all the data
-        await reader.read(READ_BUF_SIZE)
+        pass
 
     return False