Automate GitHub release workflow

[tstromberg]

This will help standardize our way out of issues like https://github.com/tinkerbell/hook/issues/75

This process should handle re-releases where there is a - suffix on the filename.

[nicklasfrahm]

I have not yet worked with in detail with this, but semantic-release could be a good option here. I will submit a PR if this makes sense for you.

[damdo]

I also think this work would be quite valuable. I commented on something similar here https://github.com/tinkerbell/hook/issues/45#issuecomment-912701618 for reference.

[mmlb]

@tstromberg do you have any more details you can provide here? Is semantic-release as mentioned by @nicklasfrahm along the lines of what you were thinking?

[jacobweinstock]

Going to close this as we are using semantic versioning and have GitHub actions that have automated the release process and a RELEASING.md with a helper script that is in line with the other repositories in the Tinkerbell org.