Follow-up from "Add webhook events for access requests"
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The following discussion from !163094 should be addressed:
- [ ] @.luke started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/163094#note_2078309997):
> **Thought**
>
> I think all of the hook triggering methods that call `#execute_hooks_for` should be in the EE module of `GroupMember` and not `Member`, since that method [only works for group memberships](https://gitlab.com/gitlab-org/gitlab/-/blob/054c2a8f1c56eed96e0a3002370db14f80fc0980/ee/app/models/ee/member.rb#L335-337). Not in this MR, though because this MR hasn't introduced the problem. We could create a follow-up.
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