Add the ability to open a draft PR with no changes

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This is a feature that exists in GitLab, and I'm quit annoyed by the fact GitHub won't let me open a PR when there are no changes. At least make it a draft one automatically and don't let me merge it.
Why would I want that feature? For example sometimes I want to start writing a PR description for the problem I'm about to solve, but I just hadn't got to commit my work yet. This happens a lot, and I find myself need to commit things I don't want just so I could open the PR. Technically, I can commit something, open a PR, revert that change, and get a PR with no changes. So why have this workaround when you can just let me open it in the first place?