Allow non-admin users to delete review requests (#29057)

Fix #14459

The following users can add/remove review requests of a PR
- the poster of the PR
- the owner or collaborators of the repository
- members with read permission on the pull requests unit

models/fixtures/repository.yml

@@ -1706,3 +1706,65 @@
   is_private: true
   status: 0
   num_issues: 0
+
+-
+  id: 60
+  owner_id: 40
+  owner_name: user40
+  lower_name: repo60
+  name: repo60
+  default_branch: main
+  num_watches: 0
+  num_stars: 0
+  num_forks: 0
+  num_issues: 0
+  num_closed_issues: 0
+  num_pulls: 1
+  num_closed_pulls: 0
+  num_milestones: 0
+  num_closed_milestones: 0
+  num_projects: 0
+  num_closed_projects: 0
+  is_private: false
+  is_empty: false
+  is_archived: false
+  is_mirror: false
+  status: 0
+  is_fork: false
+  fork_id: 0
+  is_template: false
+  template_id: 0
+  size: 0
+  is_fsck_enabled: true
+  close_issues_via_commit_in_any_branch: false
+
+-
+  id: 61
+  owner_id: 41
+  owner_name: org41
+  lower_name: repo61
+  name: repo61
+  default_branch: main
+  num_watches: 0
+  num_stars: 0
+  num_forks: 0
+  num_issues: 0
+  num_closed_issues: 0
+  num_pulls: 1
+  num_closed_pulls: 0
+  num_milestones: 0
+  num_closed_milestones: 0
+  num_projects: 0
+  num_closed_projects: 0
+  is_private: false
+  is_empty: false
+  is_archived: false
+  is_mirror: false
+  status: 0
+  is_fork: false
+  fork_id: 0
+  is_template: false
+  template_id: 0
+  size: 0
+  is_fsck_enabled: true
+  close_issues_via_commit_in_any_branch: false