Pre-Release Not Supported

Semantic Versioning requires pre-releases to have the version number followed by a hyphen and a dot separated identifiers. For example, 1.0.0-alpha.1

However, autotag removes characters after 1.0.0 in the above example. This means that Semantic Versioning will not create a pre-release tag.

My workflow:
`name: Create Tag

on: push
jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v2
- uses: butlerlogic/action-autotag@stable
with:
strategy: docker
root: /mypath
tag_suffix: -Alpha
env:
GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"`

In my Dockerfile, I set the VERSION = 1.0.0-Alpha.1