fix(images): fix registryModal [EE-2426] (#6442)

app/portainer/services/modal.service/prompt.ts

@@ -44,7 +44,7 @@ export function prompt(options: PromptOptions) {
     title: options.title,
     inputType: options.inputType,
     inputOptions: options.inputOptions,
-    buttons: confirmButtons(options.buttons),
+    buttons: options.buttons ? confirmButtons(options.buttons) : undefined,
     // casting is done because ts definition expects string=>any, but library code can emit different values, based on inputType
     callback: options.callback as (value: string) => void,
     value: options.value,

app/portainer/services/registryModalService.js

@@ -20,6 +20,8 @@ function ModalServiceFactory($q, ModalService, RegistryService) {
     const defaultValue = String(_.get(registryModel, 'Registry.Id', '0'));
 
     ModalService.selectRegistry({
+      title: 'Which registry do you want to use?',
+      inputType: 'select',
       inputOptions: options,
       value: defaultValue,
       callback: (registryId) => {