[Merge request] Update with new Lifecycle r&r and email calendar policy

Why is this change being made?

We discussed in our lifecycle marketing team call shifting the R&R for me and @dambrold . I updated the descriptions for both of us.

We are still TBD on the following items (I left templates under me, but am not tied to this and would not mind giving them up):

• Email templating
• Snippet strategy
• a/b testing process
• Email review (joint effort, but owner?)
• Kubecon, SecurityCon

Also, we are updating the policy for email calendar to make it mandatory to add by the Thursday the week before.

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