[Fix] Remove false assertion (#1222)

Author: WoosukKwon

vllm/worker/worker.py

@@ -155,8 +155,6 @@ def _prepare_inputs(
         self,
         seq_group_metadata_list: List[SequenceGroupMetadata],
     ) -> Tuple[torch.Tensor, torch.Tensor, InputMetadata]:
-        assert self.block_size is not None
-
         seq_groups: List[Tuple[List[int], SamplingParams]] = []
         input_tokens: List[int] = []
         input_positions: List[int] = []