Fix misinformation

[ger3tto]

I just noticed that MultiDiscrete would throw you errors if you actually imported it and used, because the init.py of the action parser folder names the discrete setting into "DiscreteAction", not "MultiDiscrete"

[ZealanL]

I just noticed that MultiDiscrete would throw you errors if you actually imported it and used, because the init.py of the action parser folder names the discrete setting into "DiscreteAction", not "MultiDiscrete"

This is because it is called DiscreteAction... which is what the guide says.

This does not make sense.
The action parser named DiscreteAction is multi-discrete, as the guide states.
If you try to use it, you will be using a multi-discrete action parser, which is not what the guide suggests. The guide warns against this.
Instead of suggesting a revision to my phrasing of this warning, your PR entirely removes this warning from the guide. Why?

I will remove the code formatting from MultiDiscrete in the guide to make sure it is clear that this is not the name of a class that exists, sorry if that confused you.