Add scss support - requires #53976 to be merged to work

Author: Liza K

packages/kbn-plugin-generator/sao_template/sao.js

@@ -63,6 +63,7 @@ module.exports = function({ name, targetPath, isKibanaPlugin }) {
       },
     },
     filters: {
+      'public/**/index.scss': 'generateScss',
       'public/**/*': 'generateApp',
       'server/**/*': 'generateApi',
       'translations/**/*': 'generateTranslations',
@@ -84,6 +85,7 @@ module.exports = function({ name, targetPath, isKibanaPlugin }) {
           upperCamelCaseName: name.charAt(0).toUpperCase() + camelCase(name).slice(1),
           hasUi: !!answers.generateApp,
           hasServer: !!answers.generateApi,
+          hasScss: !!answers.generateScss,
           relRoot: isKibanaPlugin ? '../../../..' : '../../..',
         },
         answers

packages/kbn-plugin-generator/sao_template/template/public/index.scss

@@ -1,3 +1,7 @@
+<%_ if (hasScss) { -%>
+import './index.scss';
+<%_ } -%>
+
 import { <%= upperCamelCaseName %>PublicPlugin } from './plugin';
 
 export function plugin() {