DRA: avoid redundant extra_refs

extra_refs without anything listed is harmless, but it's nicer
to not have it. The downside is an additional if check in the template.

Author: pohly

config/jobs/kubernetes/sig-node/dra-canary.yaml

@@ -21,7 +21,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -106,7 +105,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -193,7 +191,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -280,7 +277,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -388,7 +384,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -496,7 +491,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master

config/jobs/kubernetes/sig-node/dra-ci.yaml

@@ -19,7 +19,6 @@ periodics:
     decorate: true
     decoration_config:
       timeout: 90m
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -104,7 +103,6 @@ periodics:
     decorate: true
     decoration_config:
       timeout: 90m
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -194,7 +192,6 @@ periodics:
     decorate: true
     decoration_config:
       timeout: 90m
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -306,7 +303,6 @@ periodics:
     decorate: true
     decoration_config:
       timeout: 90m
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master

config/jobs/kubernetes/sig-node/dra-presubmit.yaml

@@ -23,7 +23,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -110,7 +109,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -198,7 +196,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -287,7 +284,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -397,7 +393,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master
@@ -507,7 +502,6 @@ presubmits:
     decoration_config:
       timeout: 90m
     path_alias: k8s.io/kubernetes
-    extra_refs:
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master

config/jobs/kubernetes/sig-node/dra.jinja

@@ -64,6 +64,7 @@ presubmits:
     {%- if not ci %}
     path_alias: k8s.io/kubernetes
     {%- endif %}
+    {%- if ci and need_kubernetes_repo or need_test_infra_repo or need_containerd_20_repo %}
     extra_refs:
     {%- if ci and need_kubernetes_repo %}
     - org: kubernetes
@@ -83,6 +84,7 @@ presubmits:
       repo: containerd
       base_ref: release/2.0
     {%- endif %}
+    {%- endif %}
     spec:
       containers:
       - image: gcr.io/k8s-staging-test-infra/kubekins-e2e:v20250714-70266d743a-master