API Project-level MR approvals: response incorrect
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### Summary
[API responds with](https://gitlab.com/api/v4/projects/15364121/approvals) `approvals_before_merge: 0`, even though there are approvers in the project.
### Steps to reproduce
1. [Create project](https://gitlab.com/nelbacha/merge-requests-approvals-api/)
1. [Add members to project](https://gitlab.com/nelbacha/merge-requests-approvals-api/-/project_members)
1. Create approval rule with `> 0` approvals
1. [Use the API](https://gitlab.com/api/v4/projects/15364121/approvals) to GET [Project-level MR approvals](https://docs.gitlab.com/ee/api/merge_request_approvals.html#project-level-mr-approvals)
### Example Project
https://gitlab.com/nelbacha/merge-requests-approvals-api
### What is the current *bug* behavior?
API responds with 0
### What is the expected *correct* behavior?
API responds with amount of approvals required
### Relevant logs and/or screenshots

### Output of checks
This bug happens on GitLab.com
https://gitlab.com/api/v4/projects/15364121/approvals
```json
{
approvers: [ ],
approver_groups: [ ],
approvals_before_merge: 0,
reset_approvals_on_push: true,
disable_overriding_approvers_per_merge_request: null,
merge_requests_author_approval: null,
merge_requests_disable_committers_approval: null
}
```
https://gitlab.com/api/v4/projects/15364121/approval_rules
```json
[
{
id: 105908,
name: "test",
rule_type: "regular",
eligible_approvers: [
{
id: 1786152,
name: "🤖 GitLab Bot 🤖",
username: "gitlab-bot",
state: "active",
avatar_url: "https://assets.gitlab-static.net/uploads/-/system/user/avatar/1786152/avatar.png",
web_url: "https://gitlab.com/gitlab-bot"
}
],
approvals_required: 1,
users: [
{
id: 1786152,
name: "🤖 GitLab Bot 🤖",
username: "gitlab-bot",
state: "active",
avatar_url: "https://assets.gitlab-static.net/uploads/-/system/user/avatar/1786152/avatar.png",
web_url: "https://gitlab.com/gitlab-bot"
}
],
groups: [ ],
contains_hidden_groups: false
}
]
```
[ZD#138851](https://gitlab.zendesk.com/agent/tickets/138851) (GitLab Internal)
issue