Adding Release Post Workflow for EMs
This change adds a page to the handbook which explains the workflow for determining if a feature will be included in a milestone release for the purposes of inclusion in the release blog post. This process was discussed in this issue #5803 (closed)
The purpose of adding this to the handbook is to give EMs a process to use until more automation can be created.
@jlenny @kencjohnston @dcroft @erushton @marin @clefelhocz1