EOCs should include a summary of their shift on the weekly SRE newsletter issue

Why is this change being made?

Closes gitlab-com/gl-infra/infrastructure#12336

In order to facilitate a more egalitarian and efficient on-call handover process, we should prefer async methods over in-person meetings. To this end, we ask that outgoing on-call SREs distill the notable highlights of their on-call week into a summary on the department weekly newsletter, so that it is easily referenced and provides a curated, consumable highlight of the issues faced for incoming on-call SREs.

Currently, the in-person on-call handover meetings we have scheduled are noted as optional for most; this change reinforces the point and with an async alternative, makes the meetings entirely optional (but still encouraged).

Author Checklist

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