Rework shields.io badges after the switch to (Github Actions & Github Container Registry)

Related to f686cf1

Author: spantaleev

README.md

@@ -1,6 +1,6 @@
 # Docker Exim Relay Image
 
-[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![GitHub Tag](https://img.shields.io/github/tag/devture/exim-relay.svg)](https://hub.docker.com/r/devture/exim-relay/) [![Docker Pulls](https://img.shields.io/docker/pulls/devture/exim-relay.svg)](https://hub.docker.com/r/devture/exim-relay/)
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![GitHub Tag](https://img.shields.io/github/tag/devture/exim-relay.svg)](https://github.com/devture/exim-relay/pkgs/container/exim-relay/versions)
 
 A lightweight Docker image for an [Exim](https://www.exim.org/) mail relay, based on the official Alpine image.