uninitialized constant Psych (NameError) at the time of installing Ruby on latest alpine linux image

I am trying to create a docker image with ruby 2.5.1. It is failing at

"rbenv install $RUBY_VERSION"

I used the following link to develop my dockerfile..

https://github.com/didlich/docker-alpine-rbenv/blob/master/Dockerfile

The above link works fine as it uses alpine 3.4 but not when using alpine 3.14. Not sure what is going on.