publish: use scp instead of rsync

.gitlab-ci.yml

@@ -28,7 +28,7 @@ publish_guide:
     - echo "$SSH_KNOWN_HOSTS" > ~/.ssh/known_hosts
     - chmod 644 ~/.ssh/known_hosts
   script:
-    - 'rsync -v angelguide_??.pdf $PUBLISHING_HOST:'
+    - 'scp -v angelguide_??.pdf $PUBLISHING_HOST:'
 #  rules:
 #    - if: '$CI_COMMIT_REF_NAME == "master"'
 #      when: on_success