cli: run-ci should have configurable admin email and password

[tiborsimko]

After adding admin email and password to cluster deploy:

$ reana-dev cluster-deploy --help | grep admin
                                --admin-email john.doe@example.org
                                --admin-password mysecretpassword
  --admin-email TEXT         Admin user email address  [required]
  --admin-password TEXT      Admin user password  [required]

Let's add it also to the run-ci wrapper so that we don't force possibly unwanted values.