updated dockerfile path

Author: sandeepgupta12

.github/workflows/_binary-build-linux.yml

@@ -204,7 +204,7 @@ jobs:
             ]}
       - name: Build Docker image for ppc64le
         run: |
-          docker build -f .ci/docker/manywheel/Dockerfile_ppc64le -t pytorch/manylinuxppc64le-builder:cpu-ppc64le-main .
+          docker build -f ./.ci/docker/manywheel/Dockerfile_ppc64le -t pytorch/manylinuxppc64le-builder:cpu-ppc64le-main .
       - name: Pull Docker image
         if: ${{ steps.filter.outputs.is-test-matrix-empty == 'False' && inputs.build_environment != 'linux-s390x-binary-manywheel' && inputs.build_environment != 'linux-ppc64le-binary-manywheel' }}
         uses: pytorch/test-infra/.github/actions/pull-docker-image@main