docker-stubs incorrectly annotates `stderr` attribute of `ContainerError` as `str`, whilst it is actually `bytes`

[shomeax]

 % pip list | grep docker
docker                        7.1.0
types-docker                  7.1.0.20240827

from errors.pyi:

class ContainerError(DockerException):
    container: Container
    exit_status: Incomplete
    command: Incomplete
    image: Incomplete
    stderr: str | None
    def __init__(self, container: Container, exit_status, command, image, stderr: str | None) -> None: ...

While actually, the only source of ContainerError is the following code in containers.py:

...

        out = None
        if logging_driver == 'json-file' or logging_driver == 'journald':
            out = container.logs(
                stdout=stdout, stderr=stderr, stream=True, follow=True
            )

        exit_status = container.wait()['StatusCode']
        if exit_status != 0:
            out = None
            if not kwargs.get('auto_remove'):
                out = container.logs(stdout=False, stderr=True)

        if remove:
            container.remove()
        if exit_status != 0:
            raise ContainerError(
                container, exit_status, command, image, out
            )
...

But, container.logs returns bytes, not string, BUG.

That causes mypy false positive in perfectly correct code:

    try:
        result = client.containers.run(
            "alpine",
            f'sh -c "echo hello"',
            remove=True,
            stdout=True,
            stderr=True,
        )
        for line in result.decode("utf-8").split("\n"):
            print(line)
    except ContainerError as exc:
        if exc.stderr:
            for line in exc.stderr.decode("utf-8").split("\n"):
                print(line)

% mypy .
...
test.py: error: "str" has no attribute "decode"; maybe "encode"?  [attr-defined]
...

[mshonichev]

still reproducing as of types-docker== 7.1.0.20250809