Raise error for upload_file_to_signed_url function

[yoland68]

• Cleaned up the upload_file_to_signed_url function and raising exceptions for errors.
• Added a new test suite for file_utils that checks the upload_file_to_signed_url function in different scenarios, both successful and failing.
• Updated tests in test_publish.py for failures when using the publish command.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Flag	Coverage Δ
unittests	44.79% <100.00%> (+1.80%)	⬆️

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Files with missing lines	Coverage Δ
comfy_cli/file_utils.py	67.04% <100.00%> (+50.91%)	⬆️

... and 1 file with indirect coverage changes