Fix URL In Gitea Actions Badge Docs

[TheBrokenRail]

The example URL given in the documentation leads to a 404.

For instance, https://your-gitea-instance.com/{owner}/{repo}/actions/workflows/{workflow_file}?branch={branch}&event={event} translates to https://gitea.thebrokenrail.com/minecraft-pi-reborn/minecraft-pi-reborn/actions/workflows/build.yml, which is a 404.

I had to check the linked GitHub docs to learn that you have to add /badge.svg to the URL.

Example: https://gitea.thebrokenrail.com/minecraft-pi-reborn/minecraft-pi-reborn/actions/workflows/build.yml/badge.svg