Making sure we are picking correct release branch (#2489)

Summary:
Making sure we are picking correct release branch
Ref: https://github.com/pytorch/vision/pull/6168

Pull Request resolved: https://github.com/pytorch/audio/pull/2489

Reviewed By: mthrok

Differential Revision: D37160145

Pulled By: atalman

fbshipit-source-id: 3e4a2208cbe47f85147573159f9adb8d6a824956

.github/workflows/build-m1-binaries.yml

@@ -6,6 +6,7 @@ on:
   push:
     branches:
       - nightly
+      - release/*
     tags:
       # NOTE: Binary build pipelines should only get triggered on release candidate builds
       # Release candidate tags look like: v1.11.0-rc1
@@ -30,6 +31,10 @@ jobs:
           if [[ ${GITHUB_REF_NAME} = *-rc[0-9]* ]]; then
             echo "CHANNEL=test" >> "$GITHUB_ENV"
           fi
+      - name: Set Release CHANNEL (for release)
+        if: ${{ (github.event_name == 'pull_request' && startsWith(github.base_ref, 'release')) || startsWith(github.ref, 'release') }}
+        run: |
+          echo "CHANNEL=test" >> "$GITHUB_ENV"
       - name: Build TorchAudio M1 wheel
         shell: arch -arch arm64 bash {0}
         env:
@@ -108,6 +113,10 @@ jobs:
           if [[ ${GITHUB_REF_NAME} = *-rc[0-9]* ]]; then
             echo "CHANNEL=test" >> "$GITHUB_ENV"
           fi
+      - name: Set Release CHANNEL (for release)
+        if: ${{ (github.event_name == 'pull_request' && startsWith(github.base_ref, 'release')) || startsWith(github.ref, 'release') }}
+        run: |
+          echo "CHANNEL=test" >> "$GITHUB_ENV"
       - name: Install conda-build and purge previous artifacts
         shell: arch -arch arm64 bash {0}
         run: |