Add schedule-only job that builds everything from source

.gitlab-ci.yml

@@ -49,3 +49,23 @@ build_no_lttng:
     - colcon test --packages-select $PACKAGES_LIST
     - colcon test-result
   <<: *global_artifacts
+
+build_from_source:
+  only:
+    - schedules
+  image: $base_image_id
+  before_script:
+    - wget https://raw.githubusercontent.com/ros2/ros2/master/ros2.repos
+    - mkdir src/
+    - vcs import src/ < ros2.repos
+    - rm -rf src/micro-ROS/
+    - vcs import --force src/ < instrumentation.repos
+    - rosdep install --from-paths src --ignore-src --rosdistro dashing -y --skip-keys "console_bridge fastcdr fastrtps libopensplice67 libopensplice69 rti-connext-dds-5.3.1 urdfdom_headers"
+  script:
+    - lttng-sessiond --daemonize
+    - colcon build --symlink-install --packages-up-to $PACKAGES_LIST
+    - . install/local_setup.sh
+    - ./build/tracetools/status
+    - colcon test --packages-select $PACKAGES_LIST
+    - colcon test-result
+  <<: *global_artifacts