B006: Case where mutable default arguments are not detected

I realized that when using Python built-in dataclasses, the following scenario is not detected:

from dataclasses import dataclass

@dataclass
class MyClass:
    val = []  # Mutable data structure

Given the presence of the dataclass decorator, the signature of the __init__ method for MyClass is the following one:

def __init__(self, val = []):

I have seen that the rule B006 is supposed to detect issues where mutable data structures are used in a function signature. This is a slightly different scenario but with the same output if this effect is not intended.
I could not find any related issue. Was this issue reported before?

Start by reproducing the dataclass example from the issue and inspect the implementation and tests for rule B006. Determine whether class attributes in dataclasses are intended to receive the same warning as mutable function defaults, then add coverage and update the rule only if that behavior is confirmed.