Pin transformers==5.0.0rc1

Signed-off-by: Tcc0403 <76503978+Tcc0403@users.noreply.github.com>

Author: Tcc0403

dev/modal/tests_bwd.py

@@ -32,7 +32,7 @@ def get_optional_dependencies():
     """Get optional dependency groups."""
     return {
         "dev": [
-            "transformers>=4.49.0",
+            "transformers==5.0.0rc1",
             "matplotlib>=3.7.2",
             "ruff>=0.12.0",
             "pytest>=7.1.2",