Update Dockerfile

Dockerfile

@@ -3,7 +3,9 @@ MAINTAINER Carlos A. Gomes <carlos.algms@gmail.com>
 
 # Add Node.js repo
 RUN \
- curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - \
+ apt-get update \
+ && apt-get install --no-install-recommends -y apt-transport-https \
+ && curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - \
  && echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list \
  && curl -sL https://deb.nodesource.com/setup_8.x | bash - \
  && apt-get install --no-install-recommends -y \  
@@ -15,7 +17,6 @@ RUN \
   git \
   yarn \
   php7.1-zip \
-  apt-transport-https \
   
   
  # Slim down image