kubernetes-backend: fix reading credentials from undefined

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/little-bats-admire.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-kubernetes-backend': patch
+---
+
+Fixed a crash reading `credentials` from `undefined`.

plugins/kubernetes-backend/src/cluster-locator/CatalogClusterLocator.ts

@@ -52,7 +52,7 @@ export class CatalogClusterLocator implements KubernetesClustersSupplier {
     return new CatalogClusterLocator(catalogApi, auth);
   }
 
-  async getClusters(options: {
+  async getClusters(options?: {
     credentials: BackstageCredentials;
   }): Promise<ClusterDetails[]> {
     const apiServerKey = `metadata.annotations.${ANNOTATION_KUBERNETES_API_SERVER}`;
@@ -71,7 +71,7 @@ export class CatalogClusterLocator implements KubernetesClustersSupplier {
       {
         filter: [filter],
       },
-      options.credentials
+      options?.credentials
         ? {
             token: (
               await this.auth.getPluginRequestToken({