feat: Load Lumo utility CSS by default (#19568)

* feat: Load Lumo utility CSS by default

The imports have been manually defined in all new starter projects for a long time so this is not supposed to break much anything

* Update flow-server/src/main/resources/plugins/application-theme-plugin/theme-generator.js

Co-authored-by: Marco Collovati <marco@vaadin.com>

---------

Co-authored-by: Marco Collovati <marco@vaadin.com>
Co-authored-by: Mikhail Shabarov <61410877+mshabarov@users.noreply.github.com>

flow-server/src/main/resources/plugins/application-theme-plugin/theme-generator.js

@@ -112,7 +112,7 @@ function writeThemeFiles(themeFolder, themeName, themeProperties, options) {
   let variable = camelCase(filename);
 
   /* LUMO */
-  const lumoImports = themeProperties.lumoImports || ['color', 'typography'];
+  const lumoImports = themeProperties.lumoImports || ['typography', 'color', 'spacing', 'badge', 'utility'] ;
   if (lumoImports) {
     lumoImports.forEach((lumoImport) => {
       imports.push(`import { ${lumoImport} } from '@vaadin/vaadin-lumo-styles/${lumoImport}.js';\n`);