Append go version to release/package file

Go plugins are built against a specific go version. If gotify updates it (like in 2.5.0), the plugin is incompatible. Since there might not be many changes to this tool, it should be possible to create multiple releases per version tag with different go version builds like 1.0.0-go1.22.0.

Luckily the masters go version is stored in build/gotify-server-go-version in the build job. We can use this to add the go version to the package registry path and to the release!