Update .gitlab-ci.yml file

.gitlab-ci.yml

@@ -42,6 +42,7 @@ unit-test-job:   # This job runs in the test stage.
     - apt-get -y update
     - apt-get -y install python3
     - source ansible/bin/activate
+    - ansible-galaxy install -r requirements.yml
     - ansible-playbook site.yml -b -l localhost
   variables:
     ANSIBLE_ROLES_PATH: "/builds/digital-preservation/"