Merge branch 'master' into patch-1

.github/workflows/build.yml

@@ -24,6 +24,11 @@ jobs:
         run: python ./.github/scripts/get_release_version.py
       - name: Build docker image
         run: |
+          if [ -z "${{ env.SAMPLE_REGISTRY }}" ]; then
+            export SAMPLE_REGISTRY=docker.io/dapriosamples
+            echo "##[set-env name=SAMPLE_REGISTRY;]$SAMPLE_REGISTRY"
+          fi
+  
           SAMPLE_LIST=(2.hello-kubernetes 3.distributed-calculator 4.pub-sub 5.bindings)
 
           for sample in "${SAMPLE_LIST[@]}"; do