Configure Renovate

[andreisilviudragnea]

I suggest using Renovate over Scala Steward because it has better Maven support.

I also suggest using branch automerge, meaning that if CI passes, Renovate commits the change in master branch directly, without creating a PR. It only creates a PR for dependency updates which fail CI.

I have been using Renovate in this configuration on all my repositories and it works flawlessly.

Fixes #23.

[andreisilviudragnea]

@evis

[andreisilviudragnea]

@rahulsinghai

[andreisilviudragnea]

@evis What do you think about this?

[evis]

@andreisilviudragnea is it enough to just add renovate.json config?

I guess that setting up https://github.com/renovatebot/github-action is needed too, isn't it?

[andreisilviudragnea]

@evis There is the option to use self-hosted Renovate or to use the Renovate GitHub app. The app needs to be installed with write access to the repository, if you want the bot to also automatically commit updates in master when CI checks pass.

I only used the Github app so far. Do you have a strong opinion about using the self-hosted variant?

[evis]

Let's try this thing out =) It should simplify and speedup release process of the plugin. Thanks!