Add stubs for flake8-docstrings (#6507)

Co-authored-by: Akuli <akuviljanen17@gmail.com>

stubs/flake8-docstrings/METADATA.toml

@@ -0,0 +1 @@
+version = "1.6.*"

stubs/flake8-docstrings/flake8_docstrings.pyi

@@ -0,0 +1,19 @@
+import argparse
+import ast
+from typing import Any, ClassVar, Generator, Iterable, Type
+
+class pep257Checker:
+    name: ClassVar[str]
+    version: ClassVar[str]
+    tree: ast.AST
+    filename: str
+    checker: Any
+    source: str
+    def __init__(self, tree: ast.AST, filename: str, lines: Iterable[str]) -> None: ...
+    @classmethod
+    def add_options(cls, parser: Any) -> None: ...
+    @classmethod
+    def parse_options(cls, options: argparse.Namespace) -> None: ...
+    def run(self) -> Generator[tuple[int, int, str, Type[Any]], None, None]: ...
+
+def __getattr__(name: str) -> Any: ...  # incomplete