azure: user CAPZ 1.21 for k/k presubmits

Author: jackfrancis

config/jobs/kubernetes/sig-cloud-provider/azure/release-master.yaml

@@ -17,7 +17,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -75,7 +75,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -135,7 +135,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -205,7 +205,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -263,7 +263,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -323,7 +323,7 @@ presubmits:
     extra_refs:
       - org: kubernetes-sigs
         repo: cluster-api-provider-azure
-        base_ref: release-1.18
+        base_ref: release-1.21
         path_alias: sigs.k8s.io/cluster-api-provider-azure
         workdir: true
       - org: kubernetes-sigs
@@ -391,7 +391,7 @@ presubmits:
     extra_refs:
     - org: kubernetes-sigs
       repo: cluster-api-provider-azure
-      base_ref: release-1.18
+      base_ref: release-1.21
       path_alias: sigs.k8s.io/cluster-api-provider-azure
       workdir: true
     - org: kubernetes-sigs