fix: update import statements for purgeCSSPlugin in documentation and source files

#1295

Author: Ffloriel

docs/guides/hugo.md

@@ -93,7 +93,7 @@ If it's not already there, add `node_modules/` to your `.gitignore` file.
 Create a `postcss.config.js` file at the project root with these contents:
 
 ```js
-import { purgeCSSPlugin } from '@fullhuman/postcss-purgecss';
+import purgeCSSPlugin from '@fullhuman/postcss-purgecss';
 
 const purgecss = purgeCSSPlugin({
   content: ["./hugo_stats.json"],

docs/plugins/postcss.md

@@ -40,7 +40,7 @@ npm i -D @fullhuman/postcss-purgecss postcss
 In `postcss.config.js`:
 
 ```js
-import { purgeCSSPlugin } from '@fullhuman/postcss-purgecss';
+import purgeCSSPlugin from '@fullhuman/postcss-purgecss';
 
 module.exports = {
   plugins: [
@@ -54,7 +54,7 @@ module.exports = {
 Using PostCSS API:
 
 ```js
-import { purgeCSSPlugin } from '@fullhuman/postcss-purgecss';
+import purgeCSSPlugin from '@fullhuman/postcss-purgecss';
 
 postcss([
   purgeCSSPlugin({

packages/postcss-purgecss/src/index.ts

@@ -127,5 +127,4 @@ const purgeCSSPlugin: postcss.PluginCreator<UserDefinedOptions> = function (
 };
 purgeCSSPlugin.postcss = true;
 
-export default purgeCSSPlugin;
-export { purgeCSSPlugin };
+export default purgeCSSPlugin;