Adding Functionality To Update Users

[sean-hickey-wf]

Description

Argilla offers the ability to create and delete users but not the ability to update a User object after it has been created. For example, if we want to update the Role of a user after they have been created (from annotator to admin for example), this is not possible without deleting and recreating the User.

This PR adds an update endpoint to the FastAPI server and also the convenience of doing this through the python sdk also Closes #<issue_number>

Type of change

• New feature (non-breaking change which adds functionality)
• Improvement (change adding some improvement to an existing functionality)

How Has This Been Tested Tests have been added at both the server and SDK level to ensure that the update method is working as expected

Checklist

• I added relevant documentation
• I followed the style guidelines of this project
• I did a self-review of my code
• I made corresponding changes to the documentation
• I confirm My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have added relevant notes to the CHANGELOG.md file (See https://keepachangelog.com/)