Fix path of pydantic_base.py

Author: holtskinner

.github/workflows/update-a2a-types.yml

@@ -9,7 +9,7 @@ on:
       - main
     paths:
       - "scripts/generate_types.sh"
-      - "src/pydantic_base.py"
+      - "src/a2a/pydantic_base.py"
     types:
       - opened
       - synchronize