[BE] Delete stale non-ephemeral runners workarounds (#164285)

As all Win runners are ephemeral, no need to cleanup leftover processes
or uninstall PyTorch at the end of the test
Pull Request resolved: https://github.com/pytorch/pytorch/pull/164285
Approved by: https://github.com/Skylion007

.github/actions/teardown-win/action.yml

@@ -23,9 +23,6 @@ runs:
       run: |
         .github\scripts\kill_active_ssh_sessions.ps1
 
-    - name: Clean up leftover processes on non-ephemeral Windows runner
-      uses: pytorch/test-infra/.github/actions/cleanup-runner@main
-
     # Cleaning up Windows workspace sometimes fails flakily with device or resource busy
     # error, meaning one or more processes haven't stopped completely yet. So trying to
     # retry this step several time similar to how checkout-pytorch GHA does

.github/workflows/_win-build.yml

@@ -84,9 +84,6 @@ jobs:
           # in https://github.com/actions/checkout/issues/1018
           git config --global core.fsmonitor false
 
-      - name: Clean up leftover processes on non-ephemeral Windows runner
-        uses: pytorch/test-infra/.github/actions/cleanup-runner@main
-
       - name: Setup SSH (Click me for login details)
         uses: pytorch/test-infra/.github/actions/setup-ssh@main
         with:

.github/workflows/_win-test.yml

@@ -77,9 +77,6 @@ jobs:
           # in https://github.com/actions/checkout/issues/1018
           git config --global core.fsmonitor false
 
-      - name: Clean up leftover processes on non-ephemeral Windows runner
-        uses: pytorch/test-infra/.github/actions/cleanup-runner@main
-
       - name: Setup SSH (Click me for login details)
         uses: pytorch/test-infra/.github/actions/setup-ssh@main
         with:
@@ -260,15 +257,6 @@ jobs:
         shell: bash
         run: python3 .github/scripts/parse_ref.py
 
-      - name: Uninstall PyTorch
-        if: always()
-        continue-on-error: true
-        shell: bash
-        run: |
-          # This step removes PyTorch installed by the test to give a clean slate
-          # to the next job
-          python3 -mpip uninstall -y torch
-
       - name: Teardown Windows
         uses: ./.github/actions/teardown-win
         if: always()