workflow: update lockfile in playground before commiting the snapshot [skip ci]

Author: haoqunjiang

scripts/prepublish.mjs

@@ -9,6 +9,7 @@ let { version } = JSON.parse(await fs.readFile('./package.json'))
 const playgroundDir = path.resolve(__dirname, '../playground/')
 cd(playgroundDir)
 
+await $`pnpm install`
 await $`git add -A .`
 try {
   await $`git commit -m "version ${version} snapshot"`