Partial download test cases fail

[tduf]

Despite my PR #179, there is still 2 test cases in failure when I run locally the test_download.py:

• test/test_download.py::test_download_partials_without_resume: expected to fail but the download succeeds.
• test/test_download.py::test_download_partials_with_resume: expected a download resuming but succeeds in one shot.

./test/wait-for-hawkbit-online && dbus-run-session -- pytest -v test/test_download.py 
Waiting for hawkbit to come up 
============================================================================================================ test session starts =============================================================================================================
platform linux -- Python 3.12.3, pytest-8.2.2, pluggy-1.5.0 -- /home/thibaud/Work/xxx/repo/rauc-hawkbit-updater/venv/bin/python3
cachedir: .pytest_cache
rootdir: /home/thibaud/Work/xxx/repo/rauc-hawkbit-updater
configfile: pytest.ini
collected 7 items                                                                                                                                                                                                                            

test/test_download.py::test_download_inexistent_location PASSED                                                                                                                                                                        [ 14%]
test/test_download.py::test_download_unallowed_location PASSED                                                                                                                                                                         [ 28%]
test/test_download.py::test_download_too_slow PASSED                                                                                                                                                                                   [ 42%]
test/test_download.py::test_download_partials_without_resume FAILED                                                                                                                                                                    [ 57%]
test/test_download.py::test_download_partials_with_resume FAILED                                                                                                                                                                       [ 71%]
test/test_download.py::test_download_slow_with_resume PASSED                                                                                                                                                                           [ 85%]
test/test_download.py::test_download_only PASSED              

Full logs:
rauc-hawkbit-updater-download-issue-full-logs.txt