StructlogProcessor fails typechecking

[AWhetter]

When typechecking the following code:

from structlog.typing import Processor

shared_processors: tuple[Processor, ...] = (
    structlog.contextvars.merge_contextvars,
    structlog.processors.add_log_level,
    structlog.processors.StackInfoRenderer(),
    structlog.dev.set_exc_info,
    structlog.processors.TimeStamper(fmt="iso", utc=True),
)

processors: list[Processor]
if sys.stderr.isatty():
    processors = [
        *shared_processors,
        structlog.dev.ConsoleRenderer(),
    ]
else:
    processors = [
        *shared_processors,
        structlog.processors.dict_tracebacks,
        ecs_logging.StructlogFormatter(),
    ]

structlog.configure(
    processors=processors,
    logger_factory=structlog.PrintLoggerFactory(),
    cache_logger_on_first_use=True,
)

mypy raises the following:

error: List item 2 has incompatible type "StructlogFormatter"; expected
"Callable[[Any, str, MutableMapping[str, Any]], Union[Mapping[str, Any], str, bytes, bytearray, tuple[Any, ...]]]"  [list-item]
            ecs_logging.StructlogFormatter(),
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: "StructlogFormatter.__call__" has type "Callable[[Arg(Any, '_'), Arg(str, 'name'), Arg(dict[str, Any], 'event_dict')], str]"

StructlogFormatter is annotated as accepting a dict[str, Any], but it needs to accept any MutableMapping[str, Any]. The code already conforms to this, so addressing this issue wil hopefully only involve updating the type annotation.