gitbook displays draft MIPs as review MIPs

[apenzk]

Issue

The MIPbook displays the categories Approved and Review. However the category Review contains Drafts as well, e.g. MIP-73, which it should not.

Solution

Adjust the script for the mipbook such that only Review PRs are considered for the Review category, not Drafts.

[franck44]

@apenzk @vpallegar I cannot see a draft category in the gitbook.
Maybe it is worth having one so we can map the three statuses (draft, review, approved) to the gitbook?

[apenzk]

not so much in favor of Drafts being displayed in the gitbook. Its a very unready stage. While the mipbook is quite outward facing