chore: Remove CUDNN dependencies

[zewenli98]

Description

Since CUDNN is no longer required by Torch-TRT, remove CUDNN dependencies.

Fixes #2795

Type of change

• This change requires a documentation update

Checklist:

• [ ] My code follows the style guidelines of this project (You can use the linters)
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas and hacks
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests to verify my fix or my feature
• [ ] New and existing unit tests pass locally with my changes
• [ ] I have added the relevant labels to my PR in so that relevant reviewers are notified