JointControllers tutorial is not visible

[francocipollone]

Environment

• Online Docs

Description

• Expected behavior:

  • https://gazebosim.org/api/sim/8/jointcontrollers.html tutorial should be listed at https://gazebosim.org/api/sim/8/tutorials.html

• Actual behavior:

  • https://gazebosim.org/api/sim/8/jointcontrollers.html is not listed in the tutorials page.

Extra info

In this PR: #2263 where the tutorial was added, the tutorials.md.in file wasn't modified in order to make this tutorial "visible"