Update AMD apex version (#6739)

.github/workflows/amd-mi200.yml

@@ -48,8 +48,6 @@ jobs:
       - name: Install (ROCm) apex
         run: |
           git clone https://github.com/ROCmSoftwarePlatform/apex.git
-          cd apex
-          git checkout torch_2.1_higher
           CURRENT_VER=$(git rev-parse HEAD)
           INSTALLED_VER=$(cat /blob/amd-apex/.venv_installed_version)
           if [[ "$CURRENT_VER" != "$INSTALLED_VER" ]]; then