Add funding field to package.json

Author: wooorm

package.json

@@ -15,6 +15,10 @@
  ],
  "repository": "wooorm/css-declarations",
  "bugs": "https://github.com/wooorm/css-declarations/issues",
+ "funding": {
+ "type": "github",
+ "url": "https://github.com/sponsors/wooorm"
+ },
  "author": "Titus Wormer <tituswormer@gmail.com> (https://wooorm.com)",
  "contributors": [
  "Titus Wormer <tituswormer@gmail.com> (https://wooorm.com)"