[jobs] Fix test_backwards_compatibility.py by pinning pydantic<2 (r…

…ay-project#37097)

This appears to be the same issue as ray-project#36990

Pinning the version in the install in `test_backwards_compatibility.sh`

Signed-off-by: e428265 <arvind.chandramouli@lmco.com>

dashboard/modules/job/tests/backwards_compatibility_scripts/test_backwards_compatibility.sh

@@ -34,8 +34,8 @@ do
     conda create -y -n "${env_name}" python="${PYTHON_VERSION}"
     conda activate "${env_name}"
 
-    pip install -U ray=="${RAY_VERSION}"
-    pip install -U ray[default]=="${RAY_VERSION}"
+    # Pin pydantic version due to: https://github.com/ray-project/ray/issues/36990.
+    pip install -U "pydantic<2" ray=="${RAY_VERSION}" ray[default]=="${RAY_VERSION}"
 
     printf "\n\n\n"
     echo "========================================================="