Document PR summary and git commit messages best practices

[a-hilaly]

We need to publish a document informing ACK developers on how to write clean and well-summarized git commit messages and PR summaries. This will help the process of code review and make the commit history less complicated to explore.

[a-hilaly]

On the same hand, we should ideally switch to a non-squash merge method for prow tide config.

[ack-bot]

Issues go stale after 90d of inactivity. Mark the issue as fresh with /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close. If this issue is safe to close now please do so with /close. Provide feedback via https://github.com/aws-controllers-k8s/community. /lifecycle stale

[a-hilaly]

/lifecycle frozen