ROS2 examples are missing navigation links and/or not named correctly

[hello-robot-shehab]

1. Docs not named correctly:

• ArUco Location is named "Example 12" even though it should be named "ArUco Locator" to match the other pages:
• Voice Teleop is duplicated three times, I assume as placeholders for the two missing docs below.

2. These examples are in the sitemap but there is no navigation to them on the docs:

• https://docs.hello-robot.com/0.3/ros2/example_10/
• https://docs.hello-robot.com/0.3/extending_stretch/custom_dof/