[UX] Change kv-cache-memory log level to debug (#25479)

Signed-off-by: Michael Goin <mgoin64@gmail.com>

vllm/v1/worker/gpu_worker.py

@@ -389,7 +389,7 @@ class Worker(WorkerBase):
                 f"utilize gpu memory. Current kv cache memory in use is "
                 f"{int(self.available_kv_cache_memory_bytes)} bytes.")
 
-            logger.info(msg)
+            logger.debug(msg)
 
         # Warm up sampler and preallocate memory buffer for logits and other
         # sampling related tensors of max possible shape to avoid memory