Add regression test for dataclass kw_only support (#7413)

Co-authored-by: Pierre Sassoulas <[email protected]>

Author: DanielNoord

doc/whatsnew/fragments/7290.false_positive

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+Pylint now understands the ``kw_only`` keyword argument for ``dataclass``.
+
+Closes #7290, closes #6550, closes #5857

tests/functional/d/dataclass_kw_only.py

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+"""Test the behaviour of the kw_only keyword."""
+
+# pylint: disable=invalid-name
+
+from dataclasses import dataclass
+
+
+@dataclass(kw_only=True)
+class FooBar:
+    """Simple dataclass with a kw_only parameter."""
+
+    a: int
+    b: str
+
+
+@dataclass(kw_only=False)
+class BarFoo(FooBar):
+    """Simple dataclass with a negated kw_only parameter."""
+
+    c: int
+
+
+BarFoo(1, a=2, b="")
+BarFoo(  # [missing-kwoa,missing-kwoa,redundant-keyword-arg,too-many-function-args]
+    1, 2, c=2
+)

tests/functional/d/dataclass_kw_only.rc

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+[testoptions]
+min_pyver=3.10

tests/functional/d/dataclass_kw_only.txt

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+missing-kwoa:24:0:26:1::Missing mandatory keyword argument 'a' in constructor call:UNDEFINED
+missing-kwoa:24:0:26:1::Missing mandatory keyword argument 'b' in constructor call:UNDEFINED
+redundant-keyword-arg:24:0:26:1::Argument 'c' passed by position and keyword in constructor call:UNDEFINED
+too-many-function-args:24:0:26:1::Too many positional arguments for constructor call:UNDEFINED