[aarch64] Add aarch64 workflow (#3553)

Summary:
# Changes
* Adding workflow for building aarch64 wheels.

Pull Request resolved: https://github.com/pytorch/audio/pull/3553

Reviewed By: hwangjeff, osalpekar

Differential Revision: D48239384

Pulled By: atalman

fbshipit-source-id: dfa00edb3fee0acaf2b83fb420eaf12bddc6980e

.github/workflows/build_wheels_aarch64_linux.yml

+name: Build Aarch64 Linux Wheels
+
+on:
+    pull_request:
+    push:
+      branches:
+        - nightly
+        - main
+        - release/*
+      tags:
+          # NOTE: Binary build pipelines should only get triggered on release candidate builds
+          # Release candidate tags look like: v1.11.0-rc1
+          - v[0-9]+.[0-9]+.[0-9]+-rc[0-9]+
+    workflow_dispatch:
+
+concurrency:
+    group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref_name }}-${{ github.ref_type == 'branch' && github.sha }}-${{ github.event_name == 'workflow_dispatch' }}
+    cancel-in-progress: true
+
+jobs:
+  generate-matrix:
+    uses: pytorch/test-infra/.github/workflows/generate_binary_build_matrix.yml@main
+    with:
+      package-type: wheel
+      os: linux-aarch64
+      test-infra-repository: pytorch/test-infra
+      test-infra-ref: main
+      with-cuda: disable
+  build:
+    needs: generate-matrix
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - repository: pytorch/audio
+            smoke-test-script: test/smoke_test/smoke_test.py
+            package-name: torchaudio
+    name: ${{ matrix.repository }}
+    uses: pytorch/test-infra/.github/workflows/build_wheels_linux.yml@main
+    with:
+      repository: ${{ matrix.repository }}
+      ref: ""
+      test-infra-repository: pytorch/test-infra
+      test-infra-ref: main
+      build-matrix: ${{ needs.generate-matrix.outputs.matrix }}
+      pre-script: ${{ matrix.pre-script }}
+      post-script: ${{ matrix.post-script }}
+      package-name: ${{ matrix.package-name }}
+      smoke-test-script: ${{ matrix.smoke-test-script }}
+      trigger-event: ${{ github.event_name }}
+      architecture: aarch64
+      setup-miniconda: false
+    secrets:
+      AWS_PYTORCH_UPLOADER_ACCESS_KEY_ID: ${{ secrets.AWS_PYTORCH_UPLOADER_ACCESS_KEY_ID }}
+      AWS_PYTORCH_UPLOADER_SECRET_ACCESS_KEY: ${{ secrets.AWS_PYTORCH_UPLOADER_SECRET_ACCESS_KEY }}