Fixed the broken link in linen_to_nnx.rst

[tilakrayal]

What does this PR do?

The URL for the Transforms guide is not working. Fixed the broken link

Fixes # (issue)

Checklist

• This PR fixes a minor issue (e.g.: typo or small bug) or improves the docs (you can dismiss the other
  checks if that's the case).
• This change is discussed in a Github issue/
  discussion (please add a
  link).
• The documentation and docstrings adhere to the
  documentation guidelines.
• This change includes necessary high-coverage tests.
  (No quality testing = no merge!)

[cgarciae]

Thanks @tilakrayal !