Add a warning when using too old golangci version

[moul]

The last release (#34) brakes all the projects using golangci-lint-action@v1 and version = v1.27 (easy fix -> bump at v1.28).

Example: moul/golang-repo-template#62

• dummy commit to trigger the CI: https://github.com/moul/golang-repo-template/pull/62/checks?check_run_id=862641477
• fix https://github.com/moul/golang-repo-template/pull/62/checks?check_run_id=862642684

What do you think about adding a more explicit warning when the user's version is older than a minimal_supported_version constant you keep updated internally in this repo?