fix: less compile (#992)

Author: yoyo837

README.md

@@ -54,6 +54,7 @@ React Select
 
 ```jsx | pure
 import Select, { Option } from 'rc-select';
+import 'rc-select/assets/index.css';
 
 export default () => (
   <Select>

package.json

@@ -33,7 +33,7 @@
     "start": "dumi dev",
     "build": "dumi build",
     "prepare": "dumi setup",
-    "compile": "father build",
+    "compile": "father build && lessc assets/index.less assets/index.css",
     "prepublishOnly": "npm run compile && np --yolo --no-publish",
     "lint": "eslint src/ docs/examples/ --ext .tsx,.ts,.jsx,.js",
     "test": "rc-test",
@@ -69,6 +69,7 @@
     "eslint": "^7.1.0",
     "father": "^4.0.0",
     "jsonp": "^0.2.1",
+    "less": "^4.2.0",
     "np": "^7.5.0",
     "prettier": "^2.7.1",
     "querystring": "^0.2.1",