Scope link to dashboard issues in group issues page
Description
We link to https://gitlab.com/dashboard/issues from group issues page (for example https://gitlab.com/groups/gitlab-org/issues). As indicated in https://gitlab.com/gitlab-org/gitlab-ce/issues/27496 this page is slow and even time outs (https://gitlab.com/gitlab-org/gitlab-ce/issues/30265). We want to rework dashboard in the long term (https://gitlab.com/gitlab-org/gitlab-ce/issues/25504), but in the short term changing the link to https://gitlab.com/dashboard/issues?assignee_id=xxxxxx is a quick win.