feat: add progressbar to upload_files() for deepset Cloud client

[tholor]

Proposed Changes:

Add a tqdm progress bar to upload_files() so that users get an better idea of the progress and remaining time until their files are uploaded to deepset Cloud.

How did you test it?

Manual testing

Notes for the reviewer

Tiny change to have a standard progress bar

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added tests that demonstrate the correct behavior of the change
• I've used the conventional commit convention for my PR title
• I documented my code
• I ran pre-commit hooks and fixed any issue

[bogdankostic]

LGTM