Use sha instead of branch

[honzajavorek]

My attempt to solve #111. Not tested, this is pure shooting into dark. My idea is we cannot create the deployment using the branch as a ref, because we delete the branch after merging. Instead, we could probably use the sha. Let's see. It's already broken, so this change cannot make it more broken. Hopefully.

The GitHub error is:

{
    'message': 'No ref found for: honzajavorek/clean-up-client',
    'documentation_url': 'https://developer.github.com/v3/repos/deployments/#create-a-deployment'
}

[abtris]

That make sense for me too. LGTM

[XVincentX]

I just received a notification for this by chance.

Let's see. It's already broken, so this change cannot make it more broken.

Best sentence ever.

[honzajavorek]

@XVincentX 👋 yeah, because Black Belt is Open Source from the very beginning 😄

[XVincentX]

I think it’s also because I was the one trying to fix the usage of deployment API back in the time, with no success! V.

[honzajavorek]

Let's see whether I'm gonna be successful in taking over your sorrow of being unsuccessful in fixing this.

[honzajavorek]

This got forgotten here 😠 Just got the error again. Merging.