Create a script to generate changelog on releases

[Raffo]

Currently we have a PR template that asks contributors to add a line to the changelog. This is done to ease the release process, but it creates the problem that whenever we merge a PR, all the other open PRs have a conflict with the changelog file.
We should create a script to automate the generation of the changelog from the GitHub API instead of relying on a manually edited file.

[seanmalloy]

/kind cleanup

[seanmalloy]

One option would be to use something like this: https://github.com/kubernetes-sigs/cluster-api/blob/master/hack/tools/release/notes.go

Which is used like this: https://github.com/kubernetes-sigs/cluster-api-provider-aws/blob/a042e87b16e09dcc6f3d112b2f29e207a4fd09a4/Makefile#L413-L415

[seanmalloy]

@Raffo and @njuettner what do you think would something like this be acceptable to you?

I might be able to work on this. Let me know what you think. Thanks!

[seanmalloy]

@vinny-sabatini is going take this on. Thanks!

[ddgenome]

There are tools that do this for you already https://go.atomist.com/catalog/skills/atomist/keep-a-changelog-skill

[Raffo]

@seanmalloy I don't have a strong preference on how it is done. The key metric that I have is "time to make a release". For a process that is as simple as ExternalDNS, it takes me 30 mins of active work plus wait for all the docker images to be built. I want to lower this time significantly such that when I have to make a release it will only take a few (single digit) minutes.
I'd be happy to review a PR to address that 👍

[vinny-sabatini]

I am hoping to work on this soon, but I don't know if I will have time until next week. I will make sure to comment here when I am ready to start working on it.

If no one picks this up before I have time to work on it, I was planning on implementing something as @seanmalloy mentioned because I am not currently a member of the kubernetes-sigs org and would not have access to add an app to this repo.

[Raffo]

If no one picks this up before I have time to work on it, I was planning on implementing something as @seanmalloy mentioned because I am not currently a member of the kubernetes-sigs org and would not have access to add an app to this repo.

Apps are tricky to add, following what @seanmalloy proposed sounds good to me.

[timja]

This is really good: https://github.com/release-drafter/release-drafter
and doesn't require an app just a GitHub action