Fix all warnings in tests/spaces

[amacati]

Description

This PR fixes all warnings emitted in tests/spaces. I started working on supporting generic Array frameworks for spaces and extensively use the spaces test suite to that end. Cleaning up the existing warnings makes it easier to catch any new errors and should be useful for others. No test functionality needs to be changed.

Edit: Now also fixes all warnings that can be fixed in tests/utils.

Type of change

• Bug fix (non-breaking change which fixes an issue)

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

[pseudo-rnd-thoughts]

Looks good, I've had it on my mind to fix those warnings for a while. Thanks for doing it

[amacati]

Sorry, I accidentally synced my main branch with the latest changes from gymnasium and discarded the ones here. Should be up again in a few minutes

[amacati]

Changes are up again. Commit 1eb4430 includes the fixes for both spaces and utils.