Use unprivileged users in arm32v7 Dockerfile (#29)

Author: LazarusX

content/dotnet-template-azure-iot-edge-module/CSharp/Dockerfile.arm32v7

@@ -10,4 +10,8 @@ RUN dotnet publish -c Release -o out
 FROM microsoft/dotnet:2.0-runtime-stretch-arm32v7
 WORKDIR /app
 COPY --from=build-env /app/out ./
+
+RUN useradd -ms /bin/bash moduleuser
+USER moduleuser
+
 ENTRYPOINT ["dotnet", "SampleModule.dll"]

content/dotnet-template-azure-iot-edge-module/FSharp/Dockerfile.arm32v7

@@ -10,4 +10,8 @@ RUN dotnet publish -c Release -o out
 FROM microsoft/dotnet:2.0-runtime-stretch-arm32v7
 WORKDIR /app
 COPY --from=build-env /app/out ./
+
+RUN useradd -ms /bin/bash moduleuser
+USER moduleuser
+
 ENTRYPOINT ["dotnet", "SampleModule.dll"]