feat: migrate POST /api/workspaces endpoint to POST /api/v1/workspaces

[jfcalvo]

Description

This PR adds a new endpoint POST /api/v1/workspace allowing the creation of new workspaces for API v1.

Changes of the new endpoint compared to the old one:

• The new endpoint returns a 201 status code instead of the 200 returned by the old endpoint.

I have added also some changes to the new token creation endpoint to return 201 instead of 200.

Closes #149

Type of change

(Please delete options that are not relevant. Remember to title the PR according to the type of change)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (change restructuring the codebase without changing functionality)
• Improvement (change adding some improvement to an existing functionality)
• Documentation update

How Has This Been Tested

• Adding new tests and manually checking the old ones pass with the new endpoint.

Checklist

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

[frascuchon]

Just a reminder.