Add empty state when user tries to view a group-level branch rule on the project level
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# Context
See https://gitlab.com/gitlab-org/gitlab/-/merge_requests/208771#note_2823214240
In https://gitlab.com/gitlab-org/gitlab/-/issues/569901 https://gitlab.com/gitlab-org/gitlab/-/merge_requests/208771, users are prevented from editing a group-level branch rule on the project level to reduce confusion. Users can still manually edit their url to navigate to a group-level branch rule page in the project-level branch rule section.
Ex: `http://gdk.test:8080/flightjs/Flight/-/settings/repository/branch_rules?branch=\*-group-level`
When users manually navigate to a group-level branch rule page inside the project-level branch rule section, display an empty state.
# Design proposal
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Current state from https://gitlab.com/gitlab-org/gitlab/-/merge_requests/208771
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<th>Proposed</th>
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{width="1223" height="693"}
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User **DOES** have permission to view group-level Protected Branches

User **DOES NOT** have permission to view group-level Protected Branches

Illustration: https://gitlab.com/gitlab-org/gitlab-svgs/blob/main/illustrations/empty-state/empty-groups-md.svg
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