Remove unecessary cuda graph. (#1664)

# What does this PR do?

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Fixes # (issue)


## Before submitting
- [ ] This PR fixes a typo or...

server/text_generation_server/models/flash_causal_lm.py

@@ -802,7 +802,7 @@ class FlashCausalLM(Model):
             try:
                 logger.info("Experimental support for Cuda Graphs is enabled")
                 # Warmup cuda graphs
-                for bs in [1, 2, 4] + [8 * i for i in range(8)]:
+                for bs in [1, 2, 4] + [8 * i for i in range(1, 9)]:
                     if self.speculate is None or self.speculate + 1 <= bs:
                         self.cuda_graph_warmup(bs, max_s, max_bt)
             except Exception: