Add a check that warmup_setps is either 0 or >= 1 (#30764)

* Add a check that warmup_setps is either 0 or >= 1

Update training_args.py to add a check that warmup_setps is either 0 or >= 1. Otherwise, raise an error.

* Update src/transformers/training_args.py
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

---------
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

src/transformers/training_args.py

@@ -1797,6 +1797,9 @@ class TrainingArguments:
                 " during training"
             )
 
+        if not isinstance(self.warmup_steps, int) or self.warmup_steps < 0 or 0 < self.warmup_steps <= 1:
+            raise ValueError("warmup_steps must be either 0 or > 1")
+
         if isinstance(self.fsdp, bool):
             self.fsdp = "full_shard" if self.fsdp else ""
         if isinstance(self.fsdp, str):