Update policy to reference emails_enabled instead of emails_disabled
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https://gitlab.com/gitlab-org/gitlab/-/issues/24733 is working on removing usages of `emails_disabled` and I think the policy should be updated for projects and groups (to cause less confusion when `emails_disabled` is deprecated for both)
The following discussion from !121585 should be addressed:
- [ ] @terrichu started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/121585#note_1424256664): (+3 comments)
> **question (non-blocking):** is there an issue to update this policy? I don't think it needs to be part of this and can be in a follow up
issue