WIP - Cloud Milestones 2023

Adding Cloud Milestones for 2023 to timeline

Cloud Milestones 2023 Chart
Cloud Report, Chapter 5 = Milestones 2023

added Progress::3_Doing to-be-discussed labels

assigned to @SpickerHZB

created branch 426-wip-cloud-milestones-2023 to address this issue

mentioned in merge request !702 (merged)

mentioned in commit 1dd225ce

closed with merge request !702 (merged)