Dockerfile in pbmenv-0.1.3 vs Dockerfile in pbmenv-0.1.4

- old
+ new

@@ -1,6 +1,7 @@
 FROM ruby:2.5
 
 WORKDIR /pbmenv
 
+ENV CI=1
 ADD docker/Gemfile .
-RUN apt-get update && apt-get install vim && gem i bundler && bundle install
+RUN apt-get update && apt-get install vim -y && gem i bundler && bundle install