docs: Add ADR for recent cert revocation and regeneration changes
docs: Add ADR for recent cert revocation and regeneration changes

[MICROBA-1080]
- Add additional context in the `invalidate` and `mark_notpassing` functions related to recent work

edx/edx-platform,edx/edx-platform,eduNEXT/edx-platform,eduNEXT/edx-platform,angelapper/edx-platform,edx/edx-platform,angelapper/edx-platform,eduNEXT/edx-platform,eduNEXT/edx-platform,arbrandes/edx-platform,arbrandes/edx-platform,angelapper/edx-platform,arbrandes/edx-platform,angelapper/edx-platform,arbrandes/edx-platform,edx/edx-platform