feat: add hex publish docs github action

[yordis]

Context

This will allow us to trigger publishing docs only from the trunk branch without creating a new release

[yordis]

Is this the best way to do it? Should I put this at the job level instead?

[btkostner]

I'd put it at the job level if statement. Easier to parse

[btkostner]

Don't the docs get published with mix hex.publish? That's ran for every release created. What's the use case for this? I'd imagine viewing hexdocs you'd want it to be the latest published version instead of things that are not yet released.

One other thing I've done before is have the main docs published to github pages so the "dev" docs are viewable

[yordis]

I'd imagine viewing hexdocs you'd want it to be the latest published version instead of things that are not yet released.

This would be for the lastest version that needs some docs refreshing, or adding extra guides and so on to hexdocs

[btkostner]

I'd put it at the job level if statement. Easier to parse

[btkostner]

If it's not a mix package this will be empty and result in null which I think GHA will error out on. You'll want this to template out to jobs: {} if it's not a mix package.

[yordis]

I'd put it at the job level if statement. Easier to pars

I remember I did that initially, but I forgot why I moved to the inside 😭

[btkostner]

Should be good