Fixes broken link for Isaac-Tracking-LocoManip-Digit-v0 (#3883)

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`Isaac-Tracking-LocoManip-Digit-v0` was moved to a different source code
path and docs were not updated accordingly. This change fixes the broken
URL.

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- Documentation update

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Author: michaellin6

docs/source/overview/environments.rst

@@ -423,7 +423,7 @@ Environments based on legged locomotion tasks.
 
 .. |velocity-flat-digit-link| replace:: `Isaac-Velocity-Flat-Digit-v0 <https://github.com/isaac-sim/IsaacLab/blob/main/source/isaaclab_tasks/isaaclab_tasks/manager_based/locomotion/velocity/config/digit/flat_env_cfg.py>`__
 .. |velocity-rough-digit-link| replace:: `Isaac-Velocity-Rough-Digit-v0 <https://github.com/isaac-sim/IsaacLab/blob/main/source/isaaclab_tasks/isaaclab_tasks/manager_based/locomotion/velocity/config/digit/rough_env_cfg.py>`__
-.. |tracking-loco-manip-digit-link| replace:: `Isaac-Tracking-LocoManip-Digit-v0 <https://github.com/isaac-sim/IsaacLab/blob/main/source/isaaclab_tasks/isaaclab_tasks/manager_based/loco_manipulation/tracking/config/digit/loco_manip_env_cfg.py>`__
+.. |tracking-loco-manip-digit-link| replace:: `Isaac-Tracking-LocoManip-Digit-v0 <https://github.com/isaac-sim/IsaacLab/blob/main/source/isaaclab_tasks/isaaclab_tasks/manager_based/locomanipulation/tracking/config/digit/loco_manip_env_cfg.py>`__
 
 .. |velocity-flat-anymal-b| image:: ../_static/tasks/locomotion/anymal_b_flat.jpg
 .. |velocity-rough-anymal-b| image:: ../_static/tasks/locomotion/anymal_b_rough.jpg