update observation space docstring for `fetch` `pick_and_place` `push` `slide` environments

[SethPate]

Description

The docstring for the observations space in the Fetch Push, Slide, PickAndPlace tasks has a typo. I didn't find a similar problem in Reach. This is only a change to the docstring.

Fixes # (issue)

Type of change

• [x] This change requires a documentation update

Screenshots

n/a

Checklist:

• [ ] I have run the pre-commit checks with pre-commit run --all-files (see CONTRIBUTING.md instructions to set it up)
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes

[Kallinteris-Andreas]

1) can you run pre-commit? 2) can you point to the code that corresponds to the changed documentation (with a perma-link) Thanks

[SethPate]

Here's the relevant code: https://github.com/Farama-Foundation/Gymnasium-Robotics/blob/f2754e19011a6ef329a40efc92dfa4bad81a22d3/gymnasium_robotics/envs/fetch/fetch_env.py#L205C1-L205C51

I'm seeing the same failure on pre-commit, not sure what would cause it to break.

[Kallinteris-Andreas]

I will merge as soon as I fix the CI situation

[Kallinteris-Andreas]

The perma-link provided in a previous post was for the oldmujoco-py based version, for context new version: https://github.com/Farama-Foundation/Gymnasium-Robotics/blob/f2754e19011a6ef329a40efc92dfa4bad81a22d3/gymnasium_robotics/envs/fetch/fetch_env.py#L314-L338