update core number (GoogleCloudPlatform#837)

Author: NuojCheng

dags/multipod/maxtext_configs_aot.py

@@ -109,10 +109,10 @@
     )
 
   # GPU AoT tests
-  cmd = f"bash MaxText/configs/a3/llama_2_7b/16vm.sh EXECUTABLE=train_compile M_COMPILE_TOPOLOGY=a3 M_COMPILE_TOPOLOGY_NUM_SLICES=16"
+  cmd = "bash MaxText/configs/a3/llama_2_7b/8vm.sh EXECUTABLE=train_compile M_COMPILE_TOPOLOGY=a3 M_COMPILE_TOPOLOGY_NUM_SLICES=8"
   stable_a3_gpu = gke_config.get_maxtext_end_to_end_gpu_gke_test_config(
       time_out_in_min=300,
-      test_name=f"maxtext-aot-a3-stable",
+      test_name="maxtext-aot-a3-stable",
       run_model_cmds=(cmd,),
       num_slices=1,
       cluster=XpkClusters.GPU_A3PLUS_CLUSTER,