Publish a 1.0.0 version

[jineshshah36]

Hi, we've been looking for a simple action that does exactly what your action does, but because it's currently only available under main, we have to fork it to ensure we have a consistent version. It would be great if you could publish a 1.0.0 version so it can be referenced as the following:

- uses: nickcharlton/diff-check@1.0.0

[nickcharlton]

Thanks for opening — I assume you noticed it was published with a tag now, but was it the README that lead you astray? It looks like when I did the release I never update it.