Feature: Automatically close PRs that are linked to an issue not marked as ready to build

The bot should automatically close PRs that are linked to an issue that is in a stage before "ready to build"

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Hi there! Thanks for your contribution to the Files repo. Unfortunately, we do not accept PRs attached to issues that aren't ready yet. Feel free to open a new PR when the issue, #issuenumber, is marked as **ready to build**!