The step to clone the application is not working using the following command : 

git clone git@github.com:redhat-developer/openshift-gitops-getting-started.git 

It is showing the following error:

git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

If there are any perquisite steps then we should mention in the documentation.