ci(build_slim_packages): reenable mac build

.github/workflows/build_slim_packages.yaml

@@ -80,7 +80,6 @@ jobs:
         name: ${{ matrix.profile}}-${{ matrix.otp }}-${{ matrix.os }}
         path: _packages/**/*.zip
   mac:
-    if: contains(github.event.pull_request.labels.*.name, 'Mac')
     strategy:
       fail-fast: false
       matrix:
@@ -139,7 +138,7 @@ jobs:
       uses: actions/cache@v2
       with:
         path: _build/default/lib/quicer/
-        key: mac-${{ matrix.otp }}-macos-${{ steps.deps-refs.outputs.DEP_QUICER_REF }}
+        key: ${{ matrix.macos }}-${{ matrix.otp }}-macos-${{ steps.deps-refs.outputs.DEP_QUICER_REF }}
     - name: build ${{ matrix.profile }}
       run: |
         . $HOME/.kerl/${{ matrix.otp }}/activate