Error : RPC failed; curl 56 OpenSSL SSL_read: Operation timed out, errno 110

I have already installed rstudio server and shiny-server on my ubuntu machine (ec2 aws). I usually code in rstudio server, drop the scripts of my shiny applications in /srv/shiny-server and go to the url of the application to see it and everything works.
Since a few days I want to go through gitlab ci/cd for versioning and to automate my work, however when I run my gitlab-ci.yml I get this error :

Being new to CI/CD, I’m having a really hard time and I’d like your help if possible. Thanks