adding node to the Dockerfile

Author: thefringeninja

Dockerfile

@@ -1,6 +1,9 @@
 FROM microsoft/dotnet:2.1.403-sdk-alpine3.7 AS build
 ARG TRAVIS_BUILD_NUMBER
 ARG MYGET_API_KEY
+
+RUN apk add nodejs --no-cache git
+
 WORKDIR /src
 
 COPY ./src/*.sln ./