chore(deps): update pnpm to v9 (#36)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

package.json

@@ -1,7 +1,7 @@
 {
  "name": "unws",
  "version": "0.2.4",
- "packageManager": "pnpm@8.15.6",
+ "packageManager": "pnpm@9.0.5",
  "description": "Unified WebSocket API for Node.js, Bun and modern browsers.",
  "license": "MIT",
  "homepage": "https://github.com/sxzz/unws#readme",