Chore: `pub-points` badge broken

[nelsonic]

Hi @matehat thanks for creating and maintaining this project! 🎉 Just spotted that the pub-point badge image shows 404 both on https://pub.dev/packages/phoenix_socket and here on GitHub:

Current Markdown:

[![pub-points](https://badges.bar/phoenix_socket/pub%20points)](https://pub.dev/packages/phoenix_socket/score)

Badge: 💔

Proposed Mardown:

![Pub Points](https://img.shields.io/pub/points/phoenix_socket?color=blue&label=pub%20points)

Badge:

Overriding the label for clarity to "pub points" and the color to blue to match other popular projects on pub.dev e.g: https://pub.dev/packages/path

Or if you prefer "stock":

Md:

![Pub Points](https://img.shields.io/pub/points/phoenix_socket)

Badge:

Via: https://github.com/badges/shields/issues/7917

Going to create a quick PR to update. 👌