publish to GPR as a postpublish step

Author: koddsson

package.json

@@ -11,7 +11,8 @@
     "prebuild": "npm run clean && npm run lint && mkdir dist",
     "build": "rollup -c && cp src/index.js.flow dist/index.umd.js.flow && cp src/index.js.flow dist/index.esm.js.flow",
     "test": "npm run build",
-    "prepublishOnly": "npm run build"
+    "prepublishOnly": "npm run build",
+    "postpublish": "npm publish --ignore-scripts --@github:registry='https://npm.pkg.github.com'"
   },
   "keywords": [
     "clipboard",