[Bug Report] RGBImgObsWrapper hardcodes highlight parameter

[thesofakillers]

Describe the bug
When using RGBImgObsWrapper on an environment initialized with highlight=False, the images in the observation will still be rendered with highlight=True. This is because True highlighting is hardcoded in RGBImgObsWrapper, instead of respecting what is set by the environment being wrapped:

Minigrid/minigrid/wrappers.py

Line 326 in 546c040

rgb_img = self.get_frame(highlight=True, tile_size=self.tile_size)

Instead of highlight=True, that should say highlight=self.env.highlight or equivalent.

Code example

from minigrid.wrappers import RGBImgObsWrapper
import gymnasium as gym
import matplotlib.pyplot as plt

env = gym.make("BabyAI-GoToLocal-v0", highlight=False)
env = RGBImgObsWrapper(env)

obs, _ = env.reset()
plt.imshow(obs['image'])

The plotted image will still show a highlight around the agent, despite us having specified not to highlight the agent's view.

System Info
Describe the characteristic of your environment:

• Describe how minigrid was installed (pip, docker, source, ...)
  pip install minigrid
• What OS/version of Linux you're using. Note that while we will accept PRs to improve Window's support, we do not officially support it.
  MacOS Catalina 10.15.7
• Python version
  3.8.16

Additional context
Perhaps related: #162, #326

Checklist

• I have checked that there is no similar issue in the repo (required)

[thesofakillers]

I can submit a PR with the proposed fix if this is welcome.

[pseudo-rnd-thoughts]

Thanks, yes that would be great.
Does highlight default to True in environments?

[thesofakillers]

Yes highlight defaults to true in environments.
See here:

Minigrid/minigrid/minigrid_env.py

Line 45 in 1eb0a70

highlight: bool = True,

I'll open a PR on Monday

EDIT: PR opened, see #388