Provide version tags to easily follow updated versions

[joerg]

Hi,

It would be great if digger provided certain version tags that follow the development and releases so the actions don't need updating that much. Tags like "stable", "lts" or "v0.6" and "v0" each following the respective releases.
Reasoning is that for most package managers it is possible to define "versions bigger than" (> 1.0.0) or lazy versioning like "~> 1.2.3", but for github actions that is not possible. Using the latest version in the develop branch is an option, but can break from time to time while strictly defining a single version like "uses: diggerhq/digger@v0.6.56" tends to require quite some maintenance in updating digger.
Something in between that allows following patches while still stable would be great.