[serve][bugfix] Clip number of retries shown in error message (#49318)

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## Why are these changes needed?

The status message should never display that serve will retry a
"negative" amount of times. This can happen if the retry counter is
larger than the failed threshold. If this is the case, just clip the
lower bound to be 0 to avoid the confusing status message.

## Related issue number
N/A
<!-- For example: "Closes #1234" -->

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Signed-off-by: akyang-anyscale <[email protected]>

python/ray/serve/_private/deployment_state.py

@@ -2052,9 +2052,10 @@ def record_replica_startup_failure(self, error_msg: str):
 
             retrying_msg = "Retrying"
             if self._failed_to_start_threshold != 0:
-                remaining_retries = (
+                remaining_retries = max(
                     self._failed_to_start_threshold
-                    - self._replica_constructor_retry_counter
+                    - self._replica_constructor_retry_counter,
+                    0,
                 )
                 retrying_msg += f" {remaining_retries} more time(s)"