The problem is with the "git server" plugin, there is a bug that causes the HTTP(S) not work https://issues.jenkins.io/browse/JENKINS-72606?jql=resolution%20is%20EMPTY%20and%20component%3D17613

To use the scriptler plugin, you must enable SSH in Jenkins itself (running SSH on the server will not work because it does not tie directly into Jenkins). After you have enabled SSH you will need to generate an RSA public key on your workstation. Then in Jenkins click on your userid in the upper right corner and select "Account". The on the left side click on "Security", scroll down and paste the contents of the "id_rsa.pub" file from you local machine into the SSH Public Keys box then save. Now to clone the scriptler repo use the synax: git clone ssh://@:/scritper.git