v3

What's Changed

• Improve transparency by @zmiklank in #17
  Main changes:
  • the action no longer has the suffix input
  • instead of suffix the input image_name is used. Even though it
    can look like it brings some duplicities, it results in more
    transparent usage of the action.
  • inputs dockerfile and dockerfile_path are merged in favor of
    input dockerfile that contains a path to a Dockerfile and the
    Dockerfile itself.

Changes are not compatible, thus v3 of build-and-push is needed.

Full Changelog: v2...v3