copy package.json to dist/ folder

Author: retrofox

packages/site-admin/package.json

@@ -12,7 +12,7 @@
 	],
 	"scripts": {
 		"clean": "tsc --build ./tsconfig.json ./tsconfig-cjs.json --clean && rm -rf dist",
-		"build": "tsc --build ./tsconfig.json ./tsconfig-cjs.json && copy-assets",
+		"build": "tsc --build ./tsconfig.json ./tsconfig-cjs.json && copy-assets && copyfiles package.json dist/",
 		"prepack": "yarn run clean && yarn run build",
 		"storybook": "sb dev"
 	},