Onboarding checklist: Define ownership transfer requirements for communication channels and social media

https://github.com/cdfoundation/toc/blob/master/process/new_project_onboarding.md needs to be updated to define steps for the social media accounts and other communication channels that are essential to project sustainability

Follow-up to https://github.com/cdfoundation/toc/pull/121/

> How about YouTube accounts and other social media: Twitter, LinkedIn, Reddit, etc. Some projects including Jenkins have them consolidated, but I am not sure the Linux Foundation wants to have access to them