Change condition for generate_docs stage in CI.

.gitlab-ci.yml

@@ -90,9 +90,9 @@ generate_docs:
     - git commit -m "Updated Swagger documentation generated"
     - git push
   rules:
-    - if: '$CI_COMMIT_TAG'
-    - if: '$CI_COMMIT_BRANCH'
-      when: never
+    - if: '$CI_COMMIT_BRANCH == "master"'
+      changes:
+        - $DEPLOYMENT_INFO_VERSION_FILE
 
 docker_image_push:
   before_script: [ ] #prevent global before_script from running