Schedule merge through Reviewpad commands

[shay2025]

Is your feature request related to a problem? Please describe.
When working on a git-backed site (static blogging frameworks like Jekyll, Hugo, and Octopress), normally the user does not want to work directly on the main branch. Ideally, the user wants to be able to finish the post or site update, check if it looks good, and schedule the release.

Describe the solution you'd like
Develop a Reviewpad command to schedule pull requests to be merged at a specific date and time:

/reviewpad schedule-merge 10/12/2022T14:00