refactor: enhance making of safe isaac gym

[Gaiejj]

Description

Safe Isaac Gym needs to read configs from outside the library. We think it would be beneficial to obtain them from the Safety-Gymnasium library. To ensure backward compatibility, we have added the functionality to read the included yaml files while retaining the original interface.

Motivation and Context

#92 mentioned this question and this PR is one of the solutions.

Types of changes

What types of changes does your code introduce? Put an x in all the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds core functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (update in the documentation)

Checklist

Go over all the following points, and put an x in all the boxes that apply.
If you are unsure about any of these, don't hesitate to ask. We are here to help!

• I have read the CONTRIBUTION guide. (required)
• My change requires a change to the documentation.
• I have updated the tests accordingly. (required for a bug fix or a new feature)
• I have updated the documentation accordingly.
• I have reformatted the code using make format. (required)
• I have checked the code using make lint. (required)
• I have ensured make test pass. (required)

[muchvo]

LGTM.