remove broken link

[rklie]

Description

This PR removes the reference to a broken link that pointed to the Write a NoSQL Database in Python tutorial. The page is hitting a 404 and it doesn't seem to be active anymore, nor archived.

Motivation and Context

The change removes a wrong reference.

Types of changes

• [x] Content Update (change which fixes an issue or updates an already existing submission)
• [ ] New Article (change which adds functionality)
• [ ] Documentation change

Checklist:

• [x] My code follows the code style of this project.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have made checks to ensure URLs and other resources are valid