The `tags_only_debian` code in livecheck's `Git` strategy was
originally introduced in Homebrew/homebrew-livecheck#131 when
livecheck was in a less mature state and relied more on internal
special-casing like this (i.e., while we worked to add appropriate
`livecheck` blocks). This logic only has the potential to be
beneficial when a formula/cask doesn't contain a `livecheck` block
but I would argue that we shouldn't be making assumptions in the
strategy around whether tags with a `debian/` prefix should be
matched or omitted. The answer depends upon the context of a given
formula/cask and should be handled with a `livecheck` block, as we
do with other situations like this.