fix(kubernetes-backend): add customResources to the config.d.ts (#25866)

Signed-off-by: Thomas Cardonne <thomas.cardonne@adevinta.com>

.changeset/silly-cycles-tan.md

@@ -0,0 +1,6 @@
+---
+'@backstage/plugin-kubernetes-backend': patch
+---
+
+Add `kubernetes.clusterLocatorMethods[].clusters[].customResources` to the configuration schema.
+This was already documented and supported by the plugin.

plugins/kubernetes-backend/config.d.ts

@@ -68,6 +68,11 @@ export interface Config {
             caData?: string;
             /** @visibility secret  */
             caFile?: string;
+            customResources?: Array<{
+              group: string;
+              apiVersion: string;
+              plural: string;
+            }>;
           }>;
         }
       | {