add alert to add gpu cards

packages/playground/src/components/node_selector/TfSelectGpu.vue

@@ -1,4 +1,5 @@
 <template>
+  <v-alert class="mb-4 mx-4" type="info" variant="tonal"> Choose GPU card to deploy your VM. </v-alert>
   <div ref="input">
     <input-tooltip
       tooltip="Please select at least one card from the available GPU cards. Note that if you have a deployment that already uses certain cards, they will not appear in the selection area. You have the option to select one or more cards.."