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Each user should follow the rule, that as soon as PR is created and it's ready for review, card should be moved to status "Ready for review". Then user or users who review PRs should move card to status "In review" to show that PR is in review process. If review is done and PR needs some adjustments, card should be moved by reviewer to status "In preparation". Once reviewer approves PR, the card will have special badge
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After PR is merged the card will be moved to status "Done" automatically.
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