[Integ-test] Add instances dimension to custom_resource tests in isolated_regions.yaml

The `instances` dimension is required after #5409

Signed-off-by: Hanwen <hanwenli@amazon.com>

Author: hanwen-cluster

tests/integration-tests/configs/isolated_regions.yaml

@@ -562,31 +562,39 @@ test-suites:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_create_invalid:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_update:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_update_invalid:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_update_tag_propagation:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_delete_out_of_band:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_delete_retain:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}
     test_cluster_custom_resource.py::test_cluster_create_with_custom_policies:
       dimensions:
         - oss: {{ OSS }}
           regions: {{ REGIONS }}
+          instances: {{ INSTANCES }}