[Discover] Minor cleanup (#90260) (#90283)

Author: Maja Grubic

src/plugins/discover/public/application/embeddable/search_embeddable.ts

@@ -308,9 +308,9 @@ export class SearchEmbeddable
     );
     if (useNewFieldsApi) {
       searchSource.removeField('fieldsFromSource');
-      const fields: Record<string, any> = { field: '*' };
+      const fields: Record<string, string> = { field: '*' };
       if (pre712) {
-        fields.include_unmapped = true;
+        fields.include_unmapped = 'true';
       }
       searchSource.setField('fields', [fields]);
     } else {

test/functional/apps/discover/_indexpattern_with_unmapped_fields.ts

@@ -22,8 +22,8 @@ export default function ({ getService, getPageObjects }: FtrProviderContext) {
 
     before(async () => {
       await esArchiver.loadIfNeeded('unmapped_fields');
-      await kibanaServer.uiSettings.replace({ defaultIndex: 'test-index-unmapped-fields' });
-      await kibanaServer.uiSettings.update({
+      await kibanaServer.uiSettings.replace({
+        defaultIndex: 'test-index-unmapped-fields',
         'discover:searchFieldsFromSource': false,
       });
       log.debug('discover');