Remove frontier omp benchmark

Author: prathi-wind

.github/workflows/bench.yml

@@ -62,14 +62,6 @@ jobs:
             device: gpu
             interface: acc
             build_script: "bash .github/workflows/frontier/build.sh gpu acc bench"
-          - cluster: frontier
-            name: Oak Ridge | Frontier (CCE)
-            group: phoenix
-            labels: frontier
-            flag: f
-            device: gpu
-            interface: omp
-            build_script: "bash .github/workflows/frontier/build.sh gpu omp bench"
     runs-on:
       group: ${{ matrix.group }}
       labels: ${{ matrix.labels }}