Fix typos in docs FrozenLake_tuto.py

[mmhamdy]

Description

Corrections for some typos found in the documentation's Tutorials section in FrozenLake_tuto.py

Type of change

• This change requires a documentation update

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]

Thanks for fixing that