Wrong documents

[LarryLiZimo]

In PlugCharger, PlugCharger-v1 is labeled to have dense reward. But this environment has no dense reward.

In https://maniskill.readthedocs.io/en/latest/api/mani_skill/envs/tasks/index.html#mani_skill.envs.tasks.PlugChargerEnv , I find that PlugCharger-v1 has no dense reward.