GitHub actions: forgot setup-buildx-action to enable cross-platform Docker builds

Author: joonas-fi

.github/workflows/build.yml

@@ -8,6 +8,8 @@ jobs:
     steps:
     - uses: actions/checkout@v2
 
+    - uses: docker/setup-buildx-action@v1
+
     - name: Build
       run: |
         curl --fail --location --silent --output bob https://function61.com/go/turbobob-latest-stable-linux-amd64 && chmod +x bob