Description of problem:

Trying to sync a container repository from a private registry, user gets this error:

pulp [1ed19a1a-3155-4dbd-a476-3ab3043494ef]: pulpcore.tasking.tasks:INFO:   File "/usr/lib/python3.11/site-packages/pulpcore/tasking/tasks.py", line 61, in _execute_task
    result = func(*args, **kwargs)
             ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulp_container/app/tasks/synchronize.py", line 41, in synchronize
    return dv.create()
           ^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/declarative_version.py", line 161, in create
    loop.run_until_complete(pipeline)
  File "/usr/lib64/python3.11/asyncio/base_events.py", line 653, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/api.py", line 220, in create_pipeline
    await asyncio.gather(*futures)
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/api.py", line 41, in _call_
    await self.run()
  File "/usr/lib/python3.11/site-packages/asgiref/sync.py", line 486, in thread_handler
    raise exc_info[1]
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/artifact_stages.py", line 186, in run
    pb.done += task.result()  # download_count
               ^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/artifact_stages.py", line 241, in _handle_content_unit
    await asyncio.gather(*downloaders_for_content)
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/models.py", line 119, in download
    raise e
  File "/usr/lib/python3.11/site-packages/pulpcore/plugin/stages/models.py", line 111, in download
    download_result = await downloader.run(extra_data=self.extra_data)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulpcore/download/http.py", line 269, in run
    return await download_wrapper()
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/backoff/_async.py", line 151, in retry
    ret = await target(*args, **kwargs)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulpcore/download/http.py", line 254, in download_wrapper
    return await self._run(extra_data=extra_data)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/pulp_container/app/downloaders.py", line 76, in _run
    response.raise_for_status()
  File "/usr/lib64/python3.11/site-packages/aiohttp/client_reqrep.py", line 1058, in raise_for_status
    raise ClientResponseError("description": "406, message='Not Acceptable', url=URL('http://myregistry.local/v2/<.....>/blobs/sha256:10568e083e87a752ed7dbb1d4bef2318af50430235861bf878538f885d9a2b5a')"} 

How reproducible: 

Always,  on the "right" registry.

Is this issue a regression from an earlier version:

Used to work until satellite 6.13

Steps to Reproduce:

1. Simple sync, from the right registry

Actual behavior:
Fail to sync repository

Expected behavior:
Sync repository successfully

Business Impact / Additional info:

QE Tracker for https://issues.redhat.com/browse/SAT-25848