[STAR-2688] Update handbook to match plans for addressing sustainability issues.
- Apply changes from STAR-2602 and corresponding forum discussion to the handbook.
- Complete steps for retiring DevOps Specialist role.
- Apply small drive-by fixes.
Tickets
Test instructions
- Changes from STAR-2602 are in 4c54b0d5. Review this commit separately and confirm that the process changes triggered by STAR-2602 are reflected in the text.
- Check preview deployment of changes for any rendering issues.
Reviewers
Edited by Tim Krones