task(devx): Set @iotaledger/devx as codeowners for the /examples dir

[lucas-tortora]

Description of change

Set @iotaledger/devx as codeowners for the /examples directory

Change checklist

Tick the boxes that are relevant to your changes, and delete any items that are not.

• I have followed the contribution guidelines for this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have checked that new and existing unit tests pass locally with my changes