add a parameter to firehose to allow selection of the type of git tag

[devoncarew]

Currently we infer the type of git tag based on whether the repo is a monorepo or a single package repo. We should add an explicit parameter for this - it would allow a single package repo to opt-into using a mono-repo tag (v1.2.3 => foo_package-v1.2.3).

cc @natebosch