libyaml-dev was removed from ruby docker images

- rails/rails@746b8ee
- docker-library/ruby#493

Author: dentarg

Dockerfile

@@ -29,7 +29,7 @@ FROM base AS build
 
 # Install packages needed to build gems
 RUN apt-get update -qq && \
-    apt-get install --no-install-recommends -y build-essential git pkg-config && \
+    apt-get install --no-install-recommends -y build-essential git pkg-config libyaml-dev && \
     rm -rf /var/lib/apt/lists /var/cache/apt/archives
 
 # Install application gems