Refactor body headers requests/aqua217

[alejandroaquintero]

• Routes /create user, and /change-password were exposing passwords as query parameters.
• Refactor User pydantic model without the password, everything else passed by query parameters, but username and password passed as OAuth2 FastAPI form data.
• This changes may affect how data in the front is passed, since we are merging this to development, changes can be tested in that aws runner.