Fix ModelSelect styles in frontend settings

packages/builder/src/components/userInterface/ModelSelect.svelte

@@ -5,9 +5,22 @@
   export let value
 </script>
 
+<div>
   <Select thin secondary wide on:change {value}>
-  <option value="" />
+    <option value="">Choose a table</option>
     {#each $backendUiStore.models as model}
       <option value={model._id}>{model.name}</option>
     {/each}
   </Select>
+</div>
+
+<style>
+  div {
+    flex: 1 1 auto;
+    display: flex;
+    flex-direction: row;
+  }
+  div :global(> *) {
+    flex: 1 1 auto;
+  }
+</style>