[CI/Build] Add timing to Model Executor Test (#25799)

Signed-off-by: 22quinn <33176974+22quinn@users.noreply.github.com>

.buildkite/test-pipeline.yaml

@@ -465,8 +465,8 @@ steps:
   commands:
     - pytest -v -s kernels/mamba
 
-- label: Model Executor Test # ???
-  timeout_in_minutes: 60
+- label: Model Executor Test # 23min
+  timeout_in_minutes: 35
   mirror_hardwares: [amdexperimental]
   source_file_dependencies:
   - vllm/model_executor