Add minimal access egde case to ldap override endpoint

ee/app/controllers/ee/groups/group_members_controller.rb

@@ -26,7 +26,7 @@ module EE
       # rubocop:disable Gitlab/ModuleWithInstanceVariables
       # rubocop: disable CodeReuse/ActiveRecord
       def override
-        member = @group.members.find_by!(id: params[:id])
+        member = membershipable_members.find_by!(id: params[:id])
         updated_member = ::Members::UpdateService.new(current_user, override_params)
           .execute(member, permission: :override)
 

ee/spec/controllers/groups/group_members_controller_spec.rb

@@ -60,10 +60,44 @@ RSpec.describe Groups::GroupMembersController do
     describe 'POST #override' do
       let(:group) { create(:group_with_ldap_group_link) }
 
-      it 'is successful' do
+      before do
         allow(Ability).to receive(:allowed?).and_call_original
         allow(Ability).to receive(:allowed?).with(user, :override_group_member, membership) { true }
+      end
+      it 'is successful' do
+
+        post :override,
+             params: {
+               group_id: group,
+               id: membership,
+               group_member: { override: true }
+             },
+             format: :js
+
+        expect(response).to have_gitlab_http_status(:ok)
+      end
+
+      context 'when user has minimal access' do
+        let(:membership) { create(:group_member, :minimal_access, source: group, user: create(:user)) }
+
+        it 'is not successful' do
+          post :override,
+               params: {
+                 group_id: group,
+                 id: membership,
+                 group_member: { override: true }
+               },
+               format: :js
 
+          expect(response).to have_gitlab_http_status(:not_found)
+        end
+
+        context 'when minimal_access_role feature is available' do
+          before do
+            stub_licensed_features(minimal_access_role: true)
+          end
+
+          it 'is successful' do
             post :override,
                  params: {
                    group_id: group,
@@ -76,6 +110,8 @@ RSpec.describe Groups::GroupMembersController do
           end
         end
       end
+    end
+  end
 
   describe 'POST request_access' do
     before do