Remove unused merge request policies on project

Recent work on regulating project-level merge request approvals settings
using compliance label has removed the need to utilize instance-level
settings in controlling the modification permission.

Some internal conditions in the project policies are also consolidated.

ee/app/policies/ee/project_policy.rb

@@ -33,27 +33,6 @@ module EE
         !PushRule.global&.commit_committer_check
       end
 
-      with_scope :global
-      condition(:owner_cannot_modify_approvers_rules) do
-        License.feature_available?(:admin_merge_request_approvers_rules) &&
-          ::Gitlab::CurrentSettings.current_application_settings
-            .disable_overriding_approvers_per_merge_request
-      end
-
-      with_scope :global
-      condition(:owner_cannot_modify_merge_request_author_setting) do
-        License.feature_available?(:admin_merge_request_approvers_rules) &&
-          ::Gitlab::CurrentSettings.current_application_settings
-            .prevent_merge_requests_author_approval
-      end
-
-      with_scope :global
-      condition(:owner_cannot_modify_merge_request_committer_setting) do
-        License.feature_available?(:admin_merge_request_approvers_rules) &&
-          ::Gitlab::CurrentSettings.current_application_settings
-            .prevent_merge_requests_committers_approval
-      end
-
       with_scope :subject
       condition(:regulated_merge_request_approval_settings) do
         License.feature_available?(:admin_merge_request_approvers_rules) &&
@@ -64,18 +43,6 @@ module EE
         @subject.feature_available?(:project_merge_request_analytics)
       end
 
-      condition(:cannot_modify_approvers_rules) do
-        regulated_merge_request_approval_settings?
-      end
-
-      condition(:cannot_modify_merge_request_author_setting) do
-        regulated_merge_request_approval_settings?
-      end
-
-      condition(:cannot_modify_merge_request_committer_setting) do
-        regulated_merge_request_approval_settings?
-      end
-
       with_scope :subject
       condition(:group_push_rules_enabled) do
         @subject.group && ::Feature.enabled?(:group_push_rules, @subject.group.root_ancestor)
@@ -267,7 +234,6 @@ module EE
         enable :update_approvers
         enable :admin_feature_flags_client
         enable :modify_approvers_rules
-        enable :modify_approvers_list
         enable :modify_auto_fix_setting
         enable :modify_merge_request_author_setting
         enable :modify_merge_request_committer_setting
@@ -346,16 +312,9 @@ module EE
         prevent :read_project
       end
 
-      rule { cannot_modify_approvers_rules }.policy do
+      rule { regulated_merge_request_approval_settings }.policy do
         prevent :modify_approvers_rules
-        prevent :modify_approvers_list
-      end
-
-      rule { cannot_modify_merge_request_author_setting }.policy do
         prevent :modify_merge_request_author_setting
-      end
-
-      rule { cannot_modify_merge_request_committer_setting }.policy do
         prevent :modify_merge_request_committer_setting
       end
 

ee/spec/policies/project_policy_spec.rb

@@ -1237,7 +1237,7 @@ RSpec.describe ProjectPolicy do
       end
     end
 
-    context 'with merge request approvers not available in license' do
+    context 'with merge request approvers rules not available in license' do
       where(:role, :regulated_setting, :admin_mode, :allowed) do
         :guest      | true  | nil    | false
         :reporter   | true  | nil    | false
@@ -1268,32 +1268,22 @@ RSpec.describe ProjectPolicy do
 
   describe ':modify_approvers_rules' do
     it_behaves_like 'merge request rules' do
-      let(:setting_name) { :disable_overriding_approvers_per_merge_request }
       let(:policy) { :modify_approvers_rules }
     end
   end
 
   describe ':modify_merge_request_author_setting' do
     it_behaves_like 'merge request rules' do
-      let(:setting_name) { :prevent_merge_requests_author_approval }
       let(:policy) { :modify_merge_request_author_setting }
     end
   end
 
   describe ':modify_merge_request_committer_setting' do
     it_behaves_like 'merge request rules' do
-      let(:setting_name) { :prevent_merge_requests_committers_approval }
       let(:policy) { :modify_merge_request_committer_setting }
     end
   end
 
-  describe ':modify_approvers_list' do
-    it_behaves_like 'merge request rules' do
-      let(:setting_name) { :disable_overriding_approvers_per_merge_request }
-      let(:policy) { :modify_approvers_list }
-    end
-  end
-
   it_behaves_like 'resource with requirement permissions' do
     let(:resource) { project }
   end